A hand impact driver converts a hammer blow into a sharp twist while pressing the tip into the screw, which is what frees a seized fastener no screwdriver will move. This is the complete list of 10 interchangeable bits in the range.
How a manual impact driver works
Inside the body is a helical cam. When the end is struck, the cam converts the axial blow into a short, violent rotation of the output square — typically a few degrees. Two things happen at once, and both matter: the shock breaks the corrosion bond holding the fastener, and the same blow drives the bit hard into the recess so it cannot climb out while the twist is applied. That combination is why it works where steady force does not.
Why the bits are different
These are not screwdriver bits with a bigger shank. They are made from a tougher, less hard steel that absorbs repeated shock by deforming slightly rather than shattering, and they are shaped to sit deep in the recess so the blow is transmitted into the fastener rather than the tip. Putting an ordinary hardened bit in an impact driver is how you get a shattered bit and fragments at speed, which is a memorable way to learn the distinction.
All 10 impact driver bits
| Tip type | Size | Teng part number | EAN |
|---|---|---|---|
| Slotted | 6 mm | 940006 | 5020385101258 |
| Slotted | 8 mm | 940008 | 5020385101265 |
| Slotted | 10 mm | 940010 | 5020385101272 |
| Slotted | 12 mm | 940012 | 5020385101289 |
| Phillips | PH4 | 930004 | 5020385101241 |
| Torx | T30 | 970030 | 5020385123366 |
| Torx | T40 | 970040 | 5020385123373 |
| Torx | T45 | 970045 | 5020385123380 |
| Torx | T50 | 970050 | 5020385123397 |
| Torx | T55 | 970055 | 5020385123403 |
Where this list comes from
Every row is read from the live Teng Tools USA catalogue on the day this page was generated — product record, part number and size taken from the record itself, never transcribed from a printed catalogue or inferred from a pattern. Tip type and size are read from each product record; the shank size is listed where the record states it. A size that has been discontinued disappears from this list rather than lingering as a part number you cannot order, which is the failure mode of every static spec sheet.
Using it without making things worse
Set the driver for the direction you want before striking it — most reverse, and discovering it was set to tighten costs you the screw. Hold it square and firmly against the fastener; a driver held at an angle transfers the blow into the edge of the recess. Strike it decisively with a heavy hammer rather than tapping repeatedly, because several light blows work-harden the fastener without breaking it free. If three good blows do nothing, the answer is heat or drilling, not a fourth.
Bits are in bits and drivers; striking tools are in striking tools.