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 hexagonal 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 hard to reach places occur much less frequently.
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.
In addition to the internal Torx profile, there is 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, already “mastered” by craftsmen.
The screwdriver is universal tool, which is indispensable when you have to work with threaded fasteners of screws, self-tapping screws, screws. Usually at home we use only two screwdrivers - a flathead and a Phillips, as the most popular. But in fact, there are many types of them, it all depends on the slot that you have to work with.
In some cases, a screwdriver is more convenient to use than a screwdriver. She doesn't need electrical energy, the tool allows you to reach hard-to-reach places. And a screwdriver costs much less, so it perfectly replaces a screwdriver, unless, of course, you have to assemble furniture in a truly industrial scale or major repairs.
We can talk a lot about the types of screwdrivers, but it’s much easier and clearer for you to imagine this diagram:
Flat or straight spline is indicated by letters SL. A well-known and very simple flat-head screwdriver. A flat blade is used when working with simple fasteners, which are often found in fastenings of lock hinges, sockets, wooden shelves. Widely used in everyday life.
Phillips - a Phillips screwdriver, which is marked with letters PH. Great for most screws and self-tapping screws, now the most common.
Marking PZ (Pozidriv) also used for Phillips screwdrivers, but with a deep slot and four additional smaller edges. Such tools are also quite widely used when assembling furniture, working with drywall, and installing various wooden structures.
Hex screwdriver is marked with letters HEX. To work with hexagonal slots, special screwdrivers with high torque are used. Their main difference is the rods bent in the shape of the letter “L”. Hexagons are actively used in the repair of electrical equipment, as well as where it is necessary to unscrew fasteners on a live object. Hexagonal splines with a pin in the center are usually called protected.
TORX. Hexagonal star slot. This is a fairly highly specialized screwdriver; such fasteners are rarely used in everyday life. However, Torxes are indispensable in service centers and various repair shops.
There is a type of TORX slot with a pin in the center. They are called protected, Security T.
As you can see from our laugh, there are more varieties of screwdrivers; we have given only the most common options. There are highly specialized ones, such as Torq-Set with an asymmetrical cross-section. Such slots, which allow powerful tightening of the screw, are used in the aviation industry.
Tri-Wing, or “trefoil”, is needed where the connection must be reliably protected from unwinding on its own, and a two-pin slot (spanner or Snake-eye) is used in public places, for example, in elevators, because it cannot be unscrewed with improvised means.
The size of the screwdriver will also be of great importance. The size is always indicated on the label, but it is often difficult to figure out this point. Amateur home craftsmen often simply say - a large or small flat-head screwdriver. Meanwhile, understanding such markings will not be difficult:
- The number 0 means that the tool shaft diameter is 4 millimeters and its length is up to 80 millimeters.
- Number 1 - rod diameter 5 millimeters, length - up to 100 millimeters.
- Number 2 - diameter 6, length - up to 120 millimeters.
- Number 3 - 8 and up to 150 millimeters, respectively.
- Number 4 - the largest screwdrivers, have a shaft diameter of 10 millimeters and a length of up to 200 millimeters.
The marking itself is usually written like this: PH3 x 150mm. That is, a Phillips screwdriver, number three - diameter 8 millimeters, the length in this case is already indicated, but this is an optional parameter.
In addition, screwdrivers can be equipped with the following capabilities:
- Screwdrivers with a dielectric coating are very useful for electricians, as they protect against electric shock.
- Another option for electricians is a screwdriver with a device for detecting hidden wiring, as well as the presence of electric current in the outlet. Such tools are also called probes and testers.
- Screwdrivers with flexible shafts, which are required for working in hard-to-reach places.
- Reversible screwdrivers with ratchet mechanism. They are needed in case of prolonged work with fasteners.
- Rods with magnetized holders. They hold a self-tapping screw or screw and are very convenient to work with, especially with small fasteners.
Nowadays you can purchase various sets of screwdrivers with replaceable nozzles. It’s convenient that they don’t take up much space; you can always choose an option for a particular slot. Sets of screwdrivers can be sold in suitcases or in such compact stands.
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 increased strength class allows increasing 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 new standard Torx Plus is even more reliable and also has an anti-vandal 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 Torx compatible - 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 slot 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).
| 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 |
| 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 success, 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 tightly into the fastener. If the tool dangles in the slot, then most likely it is selected incorrectly. This is especially true not entirely 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
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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 descent...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 line, jumped, 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 disorganized, 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, which 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.
We all use self-tapping screws when working with wood. And, of course, everyone has more than one type of them stored in a treasured box on their shelf. How could it be otherwise, because there are a great many of them on sale. Construction stores offer wide range self-tapping screws various forms, sizes and purposes. For an experienced master It’s not difficult to navigate even in such a variety: he selects the appropriate diameter and length to the weight and size of the parts being fastened. I buy a black self-tapping screw with a horn-shaped head for working on drywall, and a universal self-tapping screw for dowel fastening. Galvanized self-tapping screw will be used when internal works, and for external use, for example, for assembling a terrace - stainless steel, which will not leave brown traces of corrosion on the board. Everything here is clear and simple. However, there is one more parameter: the type of screw slot. And here questions may arise: why are there so many of them, how are they different, and which slot is better?
Let's take a look at the most popular splines.
A slot is a slot, a recess in the end surface of the screw head, designed to transmit pressure and torque from a screwdriver or power tool attachment to the body of the screw when screwing. Some craftsmen are accustomed to using the term “drive”.
Straight slot - Slotted (abbreviated as SL)
The first to appear, back in the Middle Ages, was the straight slot - Slotted. It is extremely inconvenient and a relic of the past. Judge for yourself: when tightening, it is very difficult to hold the bit or screwdriver on the straight slot coaxially with the body of the screw. As a result, the tool loses adhesion to the hardware and slips, while the equipment wears out, chips on the surface of the attached parts are common, and the master can be injured. An attempt to impart increased torque results in the straight spline breaking off.
Spline SL
Phillips slot (abbreviated PH)
The invention of the Phillips cross-head slot in the 1930s was a real breakthrough. It has become possible to position the tip of the tool strictly in the center of the slot, coaxially with the body of the hardware, so the tool now holds better and slips less often. The screwing speed has increased, and it has become possible to perform installation and disassembly without breaking the slot. The Phillips slot protects the thread from breaking due to the structure of the slots, which taper towards the bottom: when screwing is completed, when the maximum value of the twisting force is reached, the tool tip is pushed out of the slot. However, it is precisely this pushing effect that imparts additional load to the inclined walls inside the slot, contributing to their premature wear, and in order to increase the torque, it is necessary to expend significant forces pressing the tool against the screw.
PH slot
Phillips slot - Pozidriv (abbreviated as PZ)
In the 60s, a modified version of the cross slot appeared - Pozidriv (abbreviated PZ). It has 4 additional rays diverging from the center. Unlike the trapezoidal slots on the Phillips slot, the Pozidriv slots have rectangular slots, which reduces the ejection force of the bit and makes it possible to increase torque. But, again, you must remember to reduce the twisting speed at the end of installation so as not to tear off the slot.
Spline PZ
Torx slot (abbreviated as TX)
This problem is solved by modern Torx slot. It has the shape of a six-pointed star, which is why craftsmen are accustomed to calling it the Asterisk. IN everyday life you can come across such concepts as an asterisk wrench, an asterisk screwdriver (or a torx wrench, a torx screwdriver). These are keys and screwdrivers with Torx slots. When using a Torx sprocket, there is no need to limit the torque at the end of screwing. When working in confined spaces and hard-to-reach places, by using a special Torx bit (screwdriver attachment) Torx-Ball - sprockets with a ball-shaped tip, installation at an angle to the axis of the screw is possible. Unlike cross-shaped splines (PH and PZ), the torx sprocket is not clogged with paint and varnish after decorative and protective treatment of the wood surface. Torx allows you to unscrew the screw without any problems if necessary. The torx bit makes maximum contact with the surface of the head, slipping is eliminated. The Torx slot has the highest degree of torque transmission from the tool to the installed self-tapping screw. It is not surprising that it is the Torx slot that is located on the heads of structural screws (up to 600 mm long), which provide reliable fixation the most critical compounds.
Torx size or Torx number varies depending on the diameter of the screws and screws.
Torx slot
Correspondence table between screw/screw size and Torx number
So, we have found out that the TORX slot is the most productive and trouble-free - and these are precisely the qualities that are valuable for any professional.
And one more fact: on the shelves of construction hypermarkets of our northern neighbor - Finland - the most popular fastener is steel self-tapping screws and TORX screws . For example, popular self-tapping screws with a flange for thin metal sheets with a torx drive you can buy there for a long time. Torx keys, a Torx screwdriver, a set of Torx bits for any need - all this is also on sale.
We hope that, sooner or later, this trend will reach us.
Save your energy and time! Buy TORX- great solution. Choose the best from TsKI.
