Impact Driver Bits — What You Need to Know
If you’re using an impact driver, you need impact-rated screwdriver bits. Standard bits will shatter, snap, or strip under the hammering action of an impact mechanism. This guide explains why impact bits are different, how to identify them, and which sets are worth buying for each major brand.
Why Standard Bits Fail in Impact Drivers
An impact driver delivers torque through a series of rapid rotational hammer blows — typically 3,000–4,000 impacts per minute. Standard chrome vanadium (CrV) screwdriver bits are designed for continuous rotation in a standard drill/driver. They’re hard but brittle. Under repeated impact blows, they crack, shatter, or snap at the shank. At best, you’ll strip screw heads. At worst, a bit fragment can become a projectile.
Impact-rated bits are engineered differently. They use a softer, more flexible steel (typically S2 modified) that absorbs the shock of each impact without fracturing. Most impact bits also include a torsion zone — a narrow section of the bit shank that flexes under load, acting as a shock absorber between the chuck and the tip.
How to Identify Impact-Rated Bits
Impact-rated bits are easy to spot if you know what to look for. They’re typically darker in colour (black oxide or similar coating rather than shiny chrome), and most have a visible torsion zone — a slightly thinner or differently-coloured section near the middle of the bit shank. Each major brand has its own name for their impact bit range:
| Brand | Impact Bit Range | Key Feature |
|---|---|---|
| Makita | Impact Gold / Impact Black (Xtreme Torsion) | Gold or black colour, XTT torsion zone, S2 steel |
| DeWalt | Extreme Impact Torsion (DT70543T series) | Black phosphate coating, torsion zone, CNC-machined tips |
| Milwaukee | SHOCKWAVE Impact Duty | Red-tinted shank, Shock Zone geometry, custom alloy steel |
| Bosch | Impact Control | Dark grey finish, torsion zone, optimised for 18V impacts |
| Wera | Impaktor | Diamond-coated tips (BiTorsion), designed for high-torque use |
Impact Bit Sizes You’ll Actually Use
Impact drivers are most commonly used for driving screws in construction and woodwork — which means Pozidriv and Torx bits get the heaviest use. Here’s what to prioritise when building your impact bit collection:
Essential (buy these first): PZ2 impact bits — you’ll burn through these faster than any other bit. Buy them in packs of 10 or 25. PZ1 and PZ3 for smaller and larger screws respectively.
Frequently used: T25 (for decking screws and Spax-type construction screws), T20 (for general Torx screws), PH2 (for machine screws and electrical work).
Good to have: T10, T15, T30 for specific applications. Hex bits if you do furniture assembly or automotive work.
25mm vs 50mm vs Longer — Which Bit Length?
Impact bits come in several lengths. The standard 25mm bit fits directly into the impact driver chuck. Longer 50mm and 75mm bits are useful when you need extra reach — for example, driving screws into deep countersinks, through joist hangers, or in tight spaces where the driver body can’t get close to the work surface. Some jobs benefit from 100mm or 150mm bits, but these flex more under load and are harder to keep straight.
For most impact driver work, keep a supply of 25mm bits (for general use) and a few 50mm bits (for reach). Use a magnetic bit holder with 25mm bits for a good balance of reach and rigidity.
Magnetic Bit Holders for Impact Drivers
A magnetic bit holder extends the reach of a 25mm bit while holding it securely. Most impact driver users keep a bit holder permanently in the chuck. Look for one that’s impact-rated — standard bit holders can crack under impact. The best ones have a sliding sleeve that holds the screw on the bit tip, making one-handed driving much easier.
Best Impact Bit Sets by Brand
Makita B-69733 Impact Black 33-Piece Set
Makita’s Impact Black range uses Xtreme Torsion Technology for maximum durability in 18V impact drivers. This 33-piece set includes PZ1, PZ2, PZ3, PH1, PH2, PH3, Torx T10–T40, hex bits, a magnetic bit holder, and nut setters. The case is compact and well-organised. This is one of the best-value impact bit sets on the market.
DeWalt DT70543T Extreme Impact Torsion 34-Piece Set
DeWalt’s Extreme Impact Torsion bits feature CNC-machined tips for precise fit and a black phosphate coating for corrosion resistance. The 34-piece set covers all the essentials — PZ, PH, Torx, and hex — in a tough, stackable case that connects to other DeWalt TSTAK boxes. The torsion zone on these bits is one of the longest on the market, giving excellent shock absorption.
Milwaukee SHOCKWAVE Impact Duty 40-Piece Set
Milwaukee’s SHOCKWAVE line is designed specifically for their M18 and M12 impact platforms but works in any impact driver. The Shock Zone geometry absorbs the repeated impacts that destroy standard bits. This 40-piece set includes PZ, PH, Torx, hex, and square drive bits, plus magnetic bit holders. Milwaukee’s bits are among the most durable in independent testing.
Wera Impaktor Bit-Check 10-Piece
If you want premium quality in a smaller set, Wera’s Impaktor bits are the gold standard. The diamond-coated tips grip screw heads exceptionally well, reducing cam-out even in worn screws. The BiTorsion technology distributes the impact force along the full length of the bit. Available in PZ, PH, and Torx-focused sets. More expensive per bit than other brands, but they last significantly longer.
For brand-specific recommendations on which bits work best with your impact driver, see our guides for Makita, DeWalt, Milwaukee, Bosch, and Ryobi.