ISO 10664-2007 - star socket for bolts and screws. Everyday names are star, asterisk, torx.

Story

The spline was developed by Textron in 1967. The use of tight-fitting bolts and bolts of a higher strength class makes it possible to increase the load on the fasteners; accordingly, a slot was needed, which provides a higher tightening torque. However, the unpopularity of the Torx tool made it possible to use the slot also to protect devices from self-repair owners. When the tool became popular, Textron added new look slot as a vandal-proof version of Torx.

In 1990, when the patent expired, Textron developed a new standard, Torx Plus, which was even more reliable and also had a vandal-proof option.

Varieties

• Torx External. Designated as E. It is an inverted Torx - the fastener has a star-shaped head, and the tool has a corresponding recess. Typically used in cars to reduce the size of a bolt head. There is no such thing as anti-vandalism. Available in sizes E4 to E44. The size numbering does not correspond to a regular Torx - for example, an E4 key will fit a T20 bit.
• Torx Tamper Resistant (anti-vandal) is designated as TR. In the middle of the slot there is a pin and a hole corresponding to this pin in a screwdriver or key. Other names: Security Torx, pin-in Torx.

• Five-spoke Torx. One of the anti-vandal options. Found under the names 5-lobe Torx, Brigadier Pentahedron key set, sometimes Pentalobe, which is incorrect, since Pentalobe is a separate daisy-shaped slot used in Apple electronics.
• Torx Plus. Improved spline with cut off ends of the star. Designated as IP (Internal Plus), it comes in sizes from 1IP to 100IP (sometimes labeled as IP1-IP100). Partially compatible with Torx - the Torx Plus tool can work with Torx fasteners, but does not provide maximum torque. Torx tools cannot work with Torx Plus fasteners.
• Torx Plus External. External option Torx Plus. Designated as EP (External Plus), it comes in sizes from 1EP to 42EP (EP1-EP42). Also has mini variants from H7EP to H2EP.
• The anti-vandal version of Torx Plus has five arms and a pin in the center of the recess. The marking is not specified in the standard, but may appear as TS or IPR.

Markings and sizes

Keys and screwdrivers are marked T or TX with slot number - 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 27, 30, 40, 45, 50, 55, 60, 70, 80, 90, 100.

Slotted keys and screwdrivers Torx Tamper Resistant TR.

For keys and slotted screwdrivers Torx Plus the spline number is indicated first, and then instead of T or TX indicated by letters IP.

Slotted keys and screwdrivers Torx Plus Tamper Resistant after the main marking they are additionally indicated T.S..

The size is determined by the circumference described by the vertices of the tool sprocket (for the E-bolt version).

Approximate dimensions and tightening torques

Number	Size		Tightening torque	~ E Torx
	inches	mm	N m
T1	0,031"	0,81	0,02 – 0,03
T2	0,036"	0,93	0,07 – 0,09
T3	0,046"	1,10	0,14 – 0,18
T4	0,050"	1,28	0,22 – 0,28
T5	0,055"	1,42	0,43 – 0,51
T5.5
T6	0,066"	1,70	0,75 – 0,90
T7	0,078"	1,99	1,4 – 1,7
T8	0,090"	2,31	2,2 – 2,6
T9	0,098"	2,50	2,8 – 3,4
T10	0,107"	2,74	3,7 – 4,5
T15	0,128"	3,27	6,4 – 7,7
T20	0,151"	3,86	10,5 – 12,7	E4
T25	0,173"	4,43	15,9 – 19	E5
T27	0,195"	4,99	22,5 – 26,9
T30	0,216"	5,52	31,1 – 37,4	E6
T35
T40	0,260"	6,65	54,1 – 65,1	E8
T45	0,306"	7,82	86 – 103,2
T47	GM-Style
T50	0,346"	8,83	132 – 158	E10
T55	0,440"	11,22	218 – 256	E12
T60	0,519"	13,25	379 – 445	E16
T70	0,610"	15,51	630 – 700	E18
T80	0,690"	17,54	943 – 1048	E20
T90	0,784"	19,92	1334 – 1483
T100	0,871"	22,13	1843 – 2048	E24

External Torx Spline Dimensions

Number	Size		Standard bolt
	inches	mm	SAE	metric
E4	0,15"	3,8	#6	M3
E5	0,18"	4,7	#8	M4
E6	0,22"	5,6	#10	M5
E7	0,24"	6,1
E8	0,29"	7,4	1/4"	M6 & M7
E10	0,36"	9,3	5/16"	M8
E12	0,43"	11,1	3/8"	M10 & M11
E14	0,50"	12,8	7/16"	M12
E16	0,57"	14,7	1/2"
E18	0,65"	16,6	9/16"	M14
E20	0,72"	18,4	5/8"	M16
E24	0,87"	22,1	3/4"	M18 & M20
E28			7/8"	M22
E32			1"	M24 & M27
E36			1-1/8"	M30
E40			1-1/4"	M33
E44			1-3/8"	M36

Usage

Fasteners with Torx slots are usually used in technology: cars, bicycles, brake systems, various prefabricated metal structures, computer hard drives, ATMs, consumer electronics and fuel equipment.

It is unknown whether this was done on purpose or not, but the Torx sizes correlate with the sizes of the inbus keys and allow you to unscrew the torn hex slot. When a slot is torn off, a Torx tool is driven into the hole formed and, with almost one hundred percent results, allows you to unscrew the torn bolt or screw.

It should be noted that when working with Torx, the following features must be taken into account:

• The tool must fit into the fastener fairly tightly. If the tool dangles in the slot, then most likely it is selected incorrectly. This is especially true for non-standard sizes, for example, T47, which is common in cars, is almost always absent from Torx key sets and is selected as T45.
• The tool must fit fully into the slot. Given the initially tight fit, this often requires the use of an impact tool.

Failure to comply with these rules often leads to destruction of the bolt head and, as a result, to unfounded criticism of Torx.

See also

Write a review about the article "Torx"

Notes

Excerpt describing Torx

The head of the column had already descended into the ravine. The collision was supposed to happen on this side of the slope...
The remnants of our regiment, which was in action, hastily formed and retreated to the right; from behind them, dispersing the stragglers, two battalions of the 6th Jaeger approached in order. They had not yet reached Bagration, but a heavy, ponderous step could already be heard, beating in step with the entire mass of people. From the left flank, walking closest to Bagration was the company commander, a round-faced, stately man with a stupid, happy expression on his face, the same one who ran out of the booth. He, apparently, was not thinking about anything at that moment, except that he would pass by his superiors like a charmer.
With a sporty complacency, he walked lightly on his muscular legs, as if he were swimming, stretching out without the slightest effort and distinguished by this lightness from the heavy step of the soldiers who followed his step. He carried a thin, narrow sword taken out at his foot (a bent sword that did not look like a weapon) and, looking first at his superiors, then back, without losing his step, he turned flexibly with his whole strong figure. It seemed that all the forces of his soul were aimed at getting past the authorities in the best possible way, and, feeling that he was doing this job well, he was happy. “Left... left... left...”, he seemed to say internally after every step, and according to this rhythm, with variously stern faces, a wall of soldier figures, weighed down with backpacks and guns, moved, as if each of these hundreds of soldiers was mentally saying, every step of the way: “ left... left... left...". The fat major, puffing and staggering, walked around the bush along the road; the lagging soldier, out of breath, with a frightened face for his malfunction, was catching up with the company at a trot; the cannonball, pressing the air, flew over the head of Prince Bagration and his retinue and to the beat: “left - left!” hit the column. “Close!” came the swaggering voice of the company commander. The soldiers circled around something in the place where the cannonball fell; an old cavalier, a flank non-commissioned officer, falling behind near the dead, caught up with his ranks, jumped up, changed his foot, fell into step and looked back angrily. “Left... left... left...” seemed to be heard from behind the threatening silence and the monotonous sound of feet simultaneously hitting the ground.
- Well done, guys! - said Prince Bagration.
“For the sake of... wow wow wow wow!...” was heard through the ranks. The gloomy soldier walking on the left, shouting, looked back at Bagration with such an expression as if he was saying: “we know it ourselves”; the other, without looking back and as if afraid to have fun, with his mouth open, shouted and walked by.
They were ordered to stop and take off their backpacks.
Bagration rode around the ranks passing by and dismounted from his horse. He gave the Cossack the reins, took off and gave his cloak, straightened his legs and adjusted the cap on his head. The head of the French column, with officers in front, appeared from under the mountain.
"With God!" Bagration said in a firm, audible voice, turned for a moment to the front and, slightly waving his arms, with the awkward step of a cavalryman, as if working, he walked forward along the uneven field. Prince Andrey felt that some irresistible force was pulling him forward, and he experienced great happiness. [Here occurred the attack about which Thiers says: “Les russes se conduisirent vaillamment, et chose rare a la guerre, on vit deux masses d"infanterie Mariecher resolument l"une contre l"autre sans qu"aucune des deux ceda avant d "etre abordee"; and Napoleon on the island of St. Helena said: "Quelques bataillons russes montrerent de l"intrepidite." [The Russians behaved valiantly, and a rare thing in war, two masses of infantry marched decisively against each other, and neither of the two yielded until the clash." Napoleon's words: [Several Russian battalions showed fearlessness.]
The French were already getting close; Already Prince Andrei, walking next to Bagration, clearly distinguished the baldrics, red epaulettes, even the faces of the French. (He clearly saw one old French officer, who, with twisted legs in boots, was hardly walking up the hill.) Prince Bagration did not give a new order and still walked silently in front of the ranks. Suddenly, one shot cracked between the French, another, a third... and smoke spread through all the disorganized enemy ranks and gunfire crackled. Several of our men fell, including the round-faced officer, who was walking so cheerfully and diligently. But at the same instant the first shot rang out, Bagration looked back and shouted: “Hurray!”
“Hurray aa aa!” a drawn-out scream echoed along our line and, overtaking Prince Bagration and each other, our people ran down the mountain in a discordant, but cheerful and animated crowd after the upset French.

The attack of the 6th Jaeger ensured the retreat of the right flank. In the center, the action of the forgotten battery of Tushin, who managed to light Shengraben, stopped the movement of the French. The French put out the fire, carried by the wind, and gave time to retreat. The retreat of the center through the ravine was hasty and noisy; however, the troops, retreating, did not mix up their commands. But the left flank, which was simultaneously attacked and bypassed by the superior forces of the French under the command of Lannes and which consisted of the Azov and Podolsk infantry and Pavlograd hussar regiments, was upset. Bagration sent Zherkov to the general of the left flank with orders to immediately retreat.
Zherkov smartly, without removing his hand from his cap, touched his horse and galloped off. But as soon as he drove away from Bagration, his strength failed him. An insurmountable fear came over him, and he could not go where it was dangerous.
Having approached the troops of the left flank, he did not go forward, where there was shooting, but began to look for the general and commanders where they could not be, and therefore did not convey the order.
The command of the left flank belonged by seniority to the regimental commander of the very regiment that was represented at Braunau by Kutuzov and in which Dolokhov served as a soldier. The command of the extreme left flank was assigned to the commander of the Pavlograd regiment, where Rostov served, as a result of which a misunderstanding occurred. Both commanders were very irritated against each other, and while things had been going on on the right flank for a long time and the French had already begun their offensive, both commanders were busy in negotiations that were intended to insult each other. The regiments, both cavalry and infantry, were very little prepared for the upcoming task. The people of the regiments, from soldier to general, did not expect battle and calmly went about peaceful affairs: feeding horses in the cavalry, collecting firewood in the infantry.
“He is, however, older than me in rank,” said the German, a hussar colonel, blushing and turning to the adjutant who had arrived, “then leave him to do as he wants.” I cannot sacrifice my hussars. Trumpeter! Play retreat!
But things were getting to a point in a hurry. The cannonade and shooting, merging, thundered on the right and in the center, and the French hoods of the Lannes riflemen had already passed the mill dam and lined up on this side in two rifle shots. The infantry colonel walked up to the horse with a trembling gait and, climbing onto it and becoming very straight and tall, rode to the Pavlograd commander. The regimental commanders gathered with polite bows and with hidden malice in their hearts.

The simplest option is a slot. In the absence of a tool, a screw with such a head, if it is not rusted, of course, can be unscrewed with a strip of metal, a knife blade, a coin, etc. The slots are marked according to the thickness and width of the tip. For example, 4x0.5: 4 mm is the width, and 0.5 mm is the thickness of the tip. Today the slot is not as popular as it used to be. There are many good reasons for this: there is no clear fixation of the head on the bolt head, the tool comes off, there is a risk of scratching the paint on the car body or getting injured. And with rusted screws, things are even worse: the head (screwdriver blade) comes out of engagement, damaging the splined part of the screw.

An additional slot on the screw head - and we have before us, perhaps, the no less popular cross (Phillips). It’s easier to understand the dimensions here, since each profile has its own conventional number from PH000 to PH4 (PH is short for Phillips). The main advantage of cross-shaped bits over spline bits is the increased contact area of ​​the working surfaces, self-centering of the tool and the ability to work under small angle. Accordingly, you can tighten the screw with a greater torque than in the previous case without fear of damaging it.

Additional slots, but significantly smaller than the main grooves on the cross profile, distinguish the new screw head, called Pozidriv. Abbreviated designation PZ, conventional numbers in use from PZ0 to PZ4. Pozidriv, although it allows you to transmit a little more force, like Phillips, does not hold very tenaciously on the screw head, therefore, to assemble critical components and mechanisms, bolts with internal or external hexagon are used.

The range of external hexagons is very wide: from 1.5 to 80 mm. Small bolts are used to secure parts and boards in control units, and large bolts are used for the chassis.

When purchasing a tool set, a 12-point profile is preferable, since the car uses not only hexagon bolts, but also 12-point ones - for example, flywheel and cylinder head bolts on Mercedes engines.

XZN heads are designed for bolts with an internal 12-point head. They secure the starter, seat slides, cylinder heads, and auxiliary unit pulleys. The marking of these heads is not the usual metric, but conventional, with the letter M in front of the profile number. Range - from M4 to M18. There are also variants of this profile with a pin in the center (for example, the oil drain plug from transmission units on Volkswagen Group cars). Some craftsmen successfully “remove the protection” by breaking out the pin.

The choice of internal hexagons is not so wide: from 1.3 to 27 mm. These bolts have a more compact head than external hex bolts. In this case, the tool head is smaller than the outer diameter of the bolt head, and problems with loosening in hard-to-reach places arise much less often.

But the internal hexagons turned out to be not so reliable: the head often turned. The reason is not only the low quality, but also the profile features. Therefore, the capricious fasteners were replaced by the more durable and hardy Torx. Sizes - from T6 to T100; from the 6th to the 10th number they follow through one, then through five, and from the 60th to the hundredth through ten, although there are exceptions, for example T27. It is possible that intermediate sizes will be added.

With equal dimensions, the Torx profile can withstand greater loads compared to a hexagon, and the ability to turn is minimized. Such fasteners are widespread not only on foreign cars, but are already used on VAZ cars - for example, they hold the “jabot” and mating parts door locks at Kalina.

To protect components and assemblies from disassembly by unqualified (read - without special tool) personnel, some manufacturers use a “torx” with a pin in the center. It is designated Torx TR. Such a tool is used when replacing, for example, the Bosch mass air flow sensor measuring element on many cars.

Besides internal profile Torx has a similar external one. Its marking begins with the letter E, sizes from E4 to E24. There are also non-standard options, for example E11. This standard can be found in the mounting of the power unit support on the Kalina.

Not long ago, auto component manufacturers offered a profile similar to a Torx, but with five “edges” and a pin in the center. The first two letters in the marking are RT. Sizes so far range from RT10 to RT50. The range will most likely expand in the near future. The profile is also used in precision equipment, for example, massive air flow sensors - instead of the “Torx” with a pin, which has already been “mastered” by craftsmen.

Screwdrivers are basic tools for assembling/disassembling various technical mechanisms and devices. They are used for turning screws with special grooves of various types on the heads (tightening and unscrewing) . Screwdriver enlarges and transmits rotational movements hands onto a small, specially sharpened working part (slot), which is inserted into the screw head. Typically, a screwdriver consists of two parts: a handle on one side and a slot on the other. Instead of a handle, a similar function can be performed by a rotating mechanism with electric drive to make the task easier for the person working with the tool. Electric screwdrivers have become one of the popular types of power tools.

The most important thing when using screwdrivers is to choose the correct type and size of tip to match the screw head. Never use screwdrivers that are not designed to handle the specific type of screw.

There are a great many different types of screws, and in addition to using traditional type slots, new types and screwdrivers for them are periodically invented. Majority common species screwdrivers, such as flathead and Phillips, have extremely wide range applications. At the same time, less typical types are often used in certain areas. Some screwdrivers are designed for service mobile devices(phones, smartphones, MP3 players, etc.). Often, manufacturers of electronic devices nowadays use special star-shaped screws, patented under the names Torx and Pentalobe.

We'll take a closer look at the most commonly used types of screws and the appropriate screwdrivers for them.

Spline types

Flat

The original and most commonly used type of screw is one that has a single slot in the head. However, this type of fastening is losing popularity because it is the least reliable - the screwdriver often slips out of the slot and the chances of damaging the screw or screwdriver are very high.

Standard marking: SL.

Cross Phillips

Another extremely popular type of spline is the Phillips spline. Phillips slot sizes (different from screw sizes) are designated 0000, 000, 00, 0, 1, 2, 3, and 4 (in ascending order of size).

Standard marking: PH.

Cross-shaped Pozidriv ®

The pattern is similar to a Phillips cross, but has 4 additional guides. Type of screws popular in Europe. Pozidriv sizes are similar to Phillips sizes.

Standard marking: PZ.

Star Torx

A six-point screw with a head hole in the form of a six-pointed star with rounded ends. A popular type of mount in the electronics field, for automotive systems and other applications. Torx screw sizes are designated T1, T2 (or T01, T02) ... T55.

Standard marking: T.

Star-shaped Torx with anti-vandal protection

Vandal-resistant Torx screw with added tamper-proof protection is designed for applications where user intervention is not desired. Screwdrivers and wrenches for Tamper-proof Torx screws can also be used to work with regular Torx screws.

Standard marking: TxH, where x is the size.

Hex Hex

A screw with a hexagon-shaped hole that can be removed with a hex wrench or screwdriver.

Standard marking: H.

Also known as a triangular slot, it is a screw with three flat “wings” and a small triangular hole in the center. There is no specific use for Tri-wing bindings. They were once used in Nintendo products. Today, they are commonly used in electronic equipment. Tri-wing sizes are designated TRI000, TRI00, TRI0, TRI1, TRI2, TRI3, etc.

Standard marking: TRI.

Two-pin (spanner)

The screw with two round holes opposite each other is designed to avoid unauthorized access. Mainly used in electronics, in public places: restrooms, elevators, train cars, etc.

Standard marking: SP.

External types

There are also several external types of screws for box screwdrivers - female screwdriver and male screw: square, pentagon, hexagon.

The most popular type of union connections is the hexagon. You can work with it using an adjustable wrench.

Below is a table with the most commonly used screwdrivers. All screwdrivers in this series are made of Ni-Cr-Mo alloy with an oxide tip.

Model	Type	Size	Working length	Image
Pro"sKit 9SD-201A		3.0	75 mm
Pro"sKit 9SD-202A		5.0	75 mm
Pro"sKit 9SD-205A		3.0	100 mm
Pro"sKit 9SD-207A		6.0	100 mm
Pro"sKit 9SD-210A		5.0	100 mm
Pro"sKit 9SD-213A		6.0	150 mm
Pro"sKit 9SD-214A		6.0	200 mm
Pro"sKit 9SD-220A		6.0	40 mm
Pro"sKit 9SD-222A		8.0	150 mm
Pro"sKit 9SD-201B		#0	75 mm
Pro"sKit 9SD-202B		#1	75 mm
Pro"sKit 9SD-205B		#0	100 mm
Pro"sKit 9SD-207B		#2	100 mm
Pro"sKit 9SD-210B		#1	100 mm
Pro"sKit 9SD-213B		#2	150 mm
Pro"sKit 9SD-214B		#2	200 mm
Pro"sKit 9SD-216B		#1	150 mm
Pro"sKit 9SD-217B		#2	250 mm
Pro"sKit 9SD-220B		#2	40 mm
Pro"sKit 9SD-222B		#3	150 mm
Pro"sKit 9SD-200-T05H		T05H	50 mm
Pro"sKit 9SD-200-T06H		T06H	50 mm
Pro"sKit 9SD-200-T07H		T07H	50 mm
Pro"sKit 9SD-200-T08H		T08H	50 mm
Pro"sKit 9SD-200-T09H		T09H	50 mm
Pro"sKit 9SD-200-T10H		T10H	75 mm
Pro"sKit 9SD-200-T15H		T15H	75 mm

Precision screwdrivers

What is a precision screwdriver?

Screwdrivers with highly precise tips, specially sharpened to precisely fit small and extra-small screw heads, are called precision screwdrivers. This type of screwdriver is used for assembling/disassembling components when repairing small devices and gadgets such as watches, mobile phones, cameras, laptops and tablets, players, video games and other electronics.

Traditionally, precision screwdrivers and sets of such screwdrivers are used by craftsmen, good set screwdrivers are also a must-have accessory for every workshop.
The range of precision screwdrivers always includes the most commonly used types and sizes: slotted, Phillips, torx, hex. For some precision work, we need screwdrivers for special screws: TriWing, Pozidriv, spanner, etc. Apple uses a special anti-vandal screw for its products, which can be unscrewed/tightened with a Pentalobe five-pointed star screwdriver.

Torx

Torx screws are quite popular for precision applications such as computer repair, mobile device repair, electronics repair, etc. Sizes: T1, T2 (or T01, T02) ... T55.

Standard marking: T.

“Five-point anti-vandal screws” is the name of the system used by Apple for its developments. Pentalobe screw sizes include TS1 (0.8mm, used in iPhone 4, iPhone 4S, iPhone 5, iPhone 5c, iPhone 5s, iPhone 6, iPhone 6 Plus, iPhone 6S, iPhone 6S Plus, iPhone SE, iPhone 7, iPhone 7 Plus, iPhone 8, iPhone 8 Plus, iPhone X), TS4 (1.2 mm, used in MacBook Air and MacBook Pro with Retina display), and TS5 (1.5 mm, used in the 2009 MacBook Pro battery).

Standard marking: TS.

Tri-Point screws are used in the manufacture of mobile devices, electronics, etc. They have begun to be used Apple company in smartphones that were released after the iPhone 6, as well as in the Apple Watch.

Standard marking: TP/Y.

Users often prefer to use screwdrivers from Pro"sKit, which has developed a whole series of precision screwdrivers. You can choose the perfect kit for your needs. The Pro"sKit SD-081 series contains the most commonly used screwdriver types, as well as some specific types for various specialized applications . You can see the products in this series in the comparison table below.

Model	Type	Size	Working length	Image
Pro"sKit SD-081-S1		1.0	50 mm
Pro"sKit SD-081-S2		1.6	50 mm
Pro"sKit SD-081-S3		2.0	50 mm
Pro"sKit SD-081-S4		2.4	50 mm
Pro"sKit SD-081-S5		3.0	50 mm
Pro"sKit SD-081-S6		2.4	75 mm
Pro"sKit SD-081-S7		3.0	100 mm
Pro"sKit SD-081-S8		4.0	150 mm
Pro"sKit SD-081-P1		#000	50 mm
Pro"sKit SD-081-P2		#00	50 mm
Pro"sKit SD-081-P3		#0	50 mm
Pro"sKit SD-081-P4		#1	50 mm
Pro"sKit SD-081-P5		#0	75 mm
Pro"sKit SD-081-P6		#1	100 mm
Pro"sKit SD-081-P7		#1	150 mm
Pro"sKit SD-081-T1		T01	50 mm
Pro"sKit SD-081-T2		T02	50 mm
Pro"sKit SD-081-T3		T03	50 mm
Pro"sKit SD-081-T4		T04	50 mm
Pro"sKit SD-081-T5		T05	50 mm
Pro"sKit SD-081-T6		T06	50 mm
Pro"sKit SD-081-T7		T07	50 mm
Pro"sKit SD-081-T8		T08	50 mm
Pro"sKit SD-081-T9		T09	50 mm
Pro"sKit SD-081-T10		T10	50 mm
Pro"sKit SD-081-T15		T15	50 mm
Pro"sKit SD-081-T20		T20	50 mm
Pro"sKit SD-081-T5H		T05H	50 mm
Pro"sKit SD-081-T6H		T06H	50 mm
Pro"sKit SD-081-T7H		T07H	50 mm
Pro"sKit SD-081-T8H		T08H	50 mm
Pro"sKit SD-081-T9H		T09H	50 mm
Pro"sKit SD-081-T10H		T10H	50 mm
Pro"sKit SD-081-T15H		T15H	50 mm
Pro"sKit SD-081-T20H		T20H	50 mm
Pro"sKit SD-081-H1		H0.7	50 mm
Pro"sKit SD-081-H2		H0.9	50 mm
Pro"sKit SD-081-H3		H1.3	50 mm
Pro"sKit SD-081-H4		H1.5	50 mm
Pro"sKit SD-081-H5		H2.0	50 mm
Pro"sKit SD-081-H6		H2.5	50 mm
Pro"sKit SD-081-H7		H3.0	50 mm
Pro"sKit SD-081-M3		M3.0	72 mm
Pro"sKit SD-081-M3.5		M3.5	72 mm
Pro"sKit SD-081-M4		M4.0	72 mm
Pro"sKit SD-081-M4.5		M4.5	72 mm
Pro"sKit SD-081-M5		M5.0	72 mm

Pulled from Wikipedia, let it hang here, it won’t hurt anyone, I’m actually writing because I need to somehow collect all the information on the slots in one place and put it on shelves. Additions, arguments, etc. are welcome.

Everything is clear here.

SL indicating the width and (not always) thickness of the slot in millimeters.

Phillips slot (PHILLIPS and POZIDRIV)

Two types: Philips and Pozidrive

Phillips: early version.

Screwdrivers have letter marking PH with slot number - 000 (1.5 mm), 00 (2 mm), 0, 1, 2, 3, 4.
Varieties:
PHILLIPS II
ACR RIBBED PHILLIPS
PHILLIPS SQUARE-DRIV

Pozidrive: a modern version.

Screwdrivers are marked with letters PZ with slot number - 0, 1, 2, 3, 4.

Varieties:
POZISQUARE DRIV
If you use screwdrivers in the wrong slot, you can tear off the slot itself.

The head of the fastener usually has cylindrical shape with hexagonal socket. To work with splines of this type, it is used hex key(inbus key)

There is also Hex Tamper Resistant as a variation:

INBUS is an acronym In nensechskantschraube B auer u nd S chaurte - Bauer & Schaurt hexagon socket head screw

Keys and screwdrivers are marked SW with the slot size in millimeters or fractions of an inch (distance between parallel edges):

Standard metric sizes are defined in ISO 2936:2001
0.7; 0.9; 1.0; 1.25; 1.3 and 1.5
from 2 to 6 in 0.5 mm increments
from 7 to 22 in 1 mm increments
24, 25, 27, 30, 32, 36, 42 and 46 mm.

Torx (star)

Torx (Torx) is a type of slot in threaded fasteners in the shape of a six-pointed star.

Varieties:
Torx Plus, the same eggs, in profile and squarer.

Torx Tamper Resistant (anti-vandal) with pin, TR marking

Brigadier Pentahedron key set - five-beam (I couldn’t find any pictures)
TORXSTEM same shit with pictures

AudiTORX (Schkoda Zvezdochka)

Well, all sorts of exotic things:

Square (Robertson slot)

A square slot is a type of slot in threaded fasteners in the shape of a regular square. Well, actually, I won’t write about the fact that it is used for all sorts of technological holes in the automotive industry

Warm and lampy, damn the Soviet GOST

There is a possibility that you will come across a variety of Square Tamper Resistant with a pin.

Torq-Set and Tri-Wing

One-way (slotted)

Anti-vandal, screw only.

Spanner

Double prong fork. Found in elevators

Used in Chevy and GMC
Two types:
A

Spline M-profile(twelve-rayed star)

As they say specifically for Shkodochka (Volkswagen)

Tri-groove

Actually, there are more of them, but I wrote about those that I actually met in real life.

UPD. I haven’t written anything yet, but there’s a chance I’ll come across:

Pentalobe

Oddly enough, everyone saw the lyubas.

Nothing more than a slot on the pieces of Ogryzk.

Star octahedron

UPD. To help takc
FOUND!
In short, what is common from above is standardized in one way or another: there is GOST, and DIN, and in general. But then the Scandinavians begin to become crazy, since the oval head is used in Nescafe (Nespresso) and Ikea.

It's called: oval-head screws
Sold on Amazon (for coffee makers)

From available means it is fixed as follows:
adjusting it to the desired form

Proof (careful French language)

Here's another version:

By turning a bat from an aluminum rod.
A plastic tube.

sic, it’s clear what’s going on here:

Well, just by gluing the tube to the bolt:

Who, maybe add more tags? Like: cognitive and fastening?

Srach, improvements, shit-throwing and other joys of life are welcome. Additions to the text and corrections by the author are MANDATORY!

A slot is a slot on the head of a screw or screw (German: Schlitz - groove, slot), designed to transmit torque to this product from a tool (screwdriver or socket wrench).

There are splines various forms and sizes. In this article we will look at the most common types of holes and the bits intended for them.

Straight spline (SL) - the most popular and simplest form slot. It is a straight groove passing through the center of the head of the fastener. The head for fasteners with a straight slot is called a "spline" or colloquial speech: “flat”, “straight” or “minus”. The working end of the screwdriver is a wedge-shaped plate.

The disadvantage of this slot is that due to the lack of clear centering, the screwdriver often flies out of the groove, while the edges of the slot itself “break off,” which is especially typical for high protracted forces. For this reason, the flat spline is poorly suited for assembling mechanisms and precision products.

Phillips slot (PH) - a widespread type of hole in a fastener. The main varieties are the traditional Phillips and the more modern Pozidrive.

Phillips (not to be confused with the Philips brand of equipment) is the oldest and known species Phillips-head threaded fasteners and screwdrivers or bits for them.

This slot was patented and put into production by a certain Henry Phillips (H.F. Phillips), who, in turn, acquired the rights to the idea from the inventor J.P. Thompson.

In a cross-shaped slot, compared to a straight slot, the grip is strengthened, the moment of force on the axis is reduced, but still, with a “tight” entry into the material, additional efforts have to be made to hold the bit in the product.

Posidrive type slot (PZ) - is an improved version of Phillips, and is used in the production of screws and self-tapping screws for wood. In mechanical engineering and metalworking, posidrive is used much less frequently. Distinctive feature Splines are small additional recesses offset by 45 degrees relative to the main axes. They provide greater stability and protection against scrolling, although they do not completely solve it.

Posidrive screwdrivers are not pushed out of the slot when used - a more stable grip is formed, which reduces wear on the bit and the part itself.

Square splineRobertson (S.Q.) - was first produced in 1908 by the Canadian Robertson, who introduced it into production instead of a straight spline. Subsequently, he was in demand by Ford in his automobile industry until Robertson refused to sell him a license to manufacture and sell the spline, after which the sales project in the United States completely failed.

Nowadays the design of a slotted clamp with a working part of a square section is used for heads metalworking tools and in fasteners. Robertson spline designed for quick socket changes hand tools with high reliability.

Hexagon spline (HX) - type of slot of threaded fasteners in the shape of a regular hexagon. The angle between the sides is 120 degrees. The head of the fastener is usually cylindrical in shape with a hexagonal recess; to work with hexagonal slots, a screwdriver or a hexagonal bit is used.

Hexagonal screws are used in the mechanical engineering, furniture, aviation and automotive industries.

Spline typeTorx (TX) - type of slot in the shape of a six-pointed star.

This spline is capable of transmitting high torque without deforming the bit or tool. TX slotted fasteners are commonly used in automotive applications, bicycles, brake systems, various prefabricated metal structures, computer hard drives, ATMs, consumer electronics, and fuel equipment.

Thanks to the reduced radial load, tool and bit life is extended. This is achieved due to the fact that the angle between the edges is only 15 degrees. This geometry creates virtually no stress. Unlike cross profiles, TORX does not require any force to drive the screws, and there is no slipping effect, which is common, for example, in a negative slot. Thus, the force transmitted through this spline will be much greater under normal application force.

Please note that there is a difference between TORX slot and TORX PLUS: in fact, it is possible to screw a TORX PLUS screw with a TORX screwdriver, but this will lead to rapid wear of both the screwdriver and the slot itself.

TORX Tamper Resistant (TXH) prevents unintentional screw removal. The only difference with regular TORX® is the hole in the center of the bit and a small pin in the center of the screw.

Spline type 3VING denotes a special “three-bladed” type of slot for threaded fasteners and screwdrivers for them. Keys and screwdrivers are marked 3 V or TW(Tri-Wing). The 3VING spline was originally used in the aerospace industry, particularly for the assembly of wide-body aircraft, but later became used in other types of production, for example in the manufacture of electronic devices. This slot is also used in NOKIA chargers.

Spline typeTORQ- SET denotes a special “four-blade” type of slot for threaded fasteners and screwdrivers for them. Keys and screwdrivers are marked 4 V or T.S.. The 4V slot is used only in the aerospace industry, although 4V screwdrivers are commercially available.

Spline typeONE- WAY(CL) - denotes special type slot of threaded fasteners and screwdrivers for them, intended only for tightening. When you try to unscrew the slot, the bit cam immediately pops out of the groove. However, there is a socket that can unscrew the CL spline. If such a “stray” is not at hand, all that remains is to drill out a screw or, after drilling two holes in it, unscrew it with a 2P bat. ONE-WAY slotted fasteners can be used in public areas to protect structures from vandalism.

Secret slot type fork wrench (2P) - with two rectangular cams, also known as "snake eyes". The slot is not designed to transmit high tightening torque, and the force is transmitted here only through two pins, which does not allow overtightening the screw.

This type is used in elevator panels, in some waiting rooms, in subways, and also for tightening cleats in some types of shoes.

There is also a variation of the bat - with three pins, which, for example, is used in clutches of bladed weapons and firearms.

Round head hex type Hexagon Balldrive (HB) - allows you to reach hard-to-reach places at an angle of up to 25 degrees. They are quickly and completely inserted into the recess and reduce the problem of “breaking” edges.

Spline typeSpline (SP) - slot in the form of a twelve-pointed star. The tightening force is evenly distributed across all rays of the star, providing the ability to transmit a high tightening torque.

That's why this type The spline is widely used for tightening cylinder heads and other engine connections.

A feature of the SP type is a tight fit and maximum coincidence of the contours of the bit and the product, therefore, if dirt and dust particles get inside the bolt, the bit deviates from the axis and can cut off the inner edges of the product and its teeth.

Triangular head slot (TR) - a type of security slot used by railways, fire services, and also in radio electronics.

The design is an equilateral triangle. The spline is not designed to transmit high torque due to its small area.