A bits and drivers setup replaces a drawer of single-purpose screwdrivers with one handle and a set of tips, and the choice comes down to three questions. Does the bit have to survive an impact driver, or only hand torque? Does the fastener sit somewhere a straight driver can reach? And does the tip actually match the recess, rather than nearly matching it? Get those three right and you will strip fewer heads, carry less, and stop rounding out the one fastener that is holding up the whole job. Get the first one wrong and a standard bit shatters in an impact driver, usually with half of it left in the screw. This guide covers the driver types Teng Tools makes, what each is genuinely good at, and how to pick sizes that cover real work rather than filling a case.
What is the difference between a screwdriver bit and an impact bit?
Hardness and torsion. A standard screwdriver bit is hardened for edge retention, which makes it precise and relatively brittle. An impact bit is built to absorb the sudden torque spikes and hammer blows an impact driver or impact wrench delivers, flexing slightly instead of snapping. Put a standard bit in an impact driver and it will eventually shear, and the failure is usually in the fastener rather than in your hand. Impact bits come in 30 mm and 50 mm lengths across the common patterns, with the longer version reaching into recessed or counterbored fixings. On stubborn, rusted or thread-locked automotive fasteners the impact bit is not a nicety, it is the difference between removing the fastener and drilling it out. Two practical rules follow. First, keep impact bits physically separate from hand bits, in their own tray, because they are hard to tell apart under workshop light and the mistake only shows when something breaks. Second, replace an impact bit as soon as the tip shows rounding, because a worn bit transfers its wear to the fastener recess and turns a five-minute job into an extraction. Both types live in the bits and drivers range.
Which driver do you need for the space you are working in?
Access decides this more often than torque does. A full-length screwdriver is the fastest tool for anything open, and completely useless six inches inside a wheel arch. Each of the shorter or articulated options trades something away to get in there, so it is worth knowing what the trade is before you buy.
| Driver | Use it when | Trade-off |
|---|---|---|
| Nut driver | Hex nuts and bolt heads in open access, repetitive work | Limited to the socket size on the shaft |
| Stubby ratcheting bit driver | Confined spaces where a handle cannot turn a full rotation | Short body means less leverage |
| Flexible extension bar | Fastener is offset behind an obstruction | Flex costs torque; hand-tighten only |
| Bit holder in a ratchet | High torque on an accessible fastener | Bulkier than a driver handle |
Nut drivers
A nut driver is a socket on a screwdriver shaft, and it is far quicker than a wrench for small fasteners you are turning many times. The Teng Tools metric set runs 5, 5.5, 6, 7, 8, 10, 11, 12 and 13 mm in chrome vanadium, with six-point ends that seat fully on the flats rather than the corners. The handles are bi-material for grip with oily hands, and each one is drilled through so it can be hung, used with a fall-arrest lanyard when working at height, or turned as a T-handle when you need two-handed control on a tight fastener.
Stubby ratcheting bit drivers
At about 100 mm overall, a stubby ratcheting driver fits where nothing else will, and the ratchet means you never have to release and reposition. The Teng Tools version has forward, reverse and fixed settings, a magnet that holds both the bit and the screw so you can start a fastener one-handed in a blind location, and bit storage inside the handle. It is supplied with six bits and a 1/4 inch square drive adaptor, so the same handle drives sockets as well as bits.
Flexible extension bars
A flexible extension bar bends around an obstruction to reach a fastener that is not in line with your hand. Teng Tools makes them in 1/4 inch hex drive at 6 inch and 12 inch (300 mm) lengths. Treat them as access tools, not torque tools: the flex that gets you to the fastener also absorbs the force you apply, so use one to run a fastener down and finish it with something rigid.
How do you stop stripping screw heads?
Almost every stripped head is a fitment problem rather than a force problem. Phillips and Pozidriv look nearly identical and are not interchangeable; a PH bit in a PZ recess contacts on a fraction of the available surface and cams out under load, and the reverse rounds the recess from the inside. Pozidriv recesses carry four small tick marks between the main slots, and it is worth learning to spot them because European vehicles and appliances are full of them. Torx and hex fasteners are less forgiving still, since a size down engages just enough to feel right and then rounds the socket completely. Four habits fix most of it. Match the pattern first and the size second, seat the bit fully before applying any turning force, keep the driver axis in line with the fastener rather than angled, and retire bits that show any tip rounding instead of persevering with them. Keeping bits in a foam tray rather than loose in a drawer helps more than it sounds like it should, because a marked, sized position makes it obvious when you have grabbed a PH2 for a PZ2 job. For Torx and hex work, the dedicated hex and TX keys give better engagement than a bit and driver, and the screwdriver range covers the jobs where a fixed blade is simply faster.