A hex driver has a six-sided tip that fits the hex-head screws used on most RC cars. Having the right sizes lets you work on the whole car without stripping screws.

The most common are 1.5, 2.0 and 2.5 mm, which cover the majority of RC screws. Check your car’s manual for the exact sizes it uses.

Tips wear with use and wear faster if you use the wrong size. Many quality drivers take replacement tips, so you can renew them instead of buying a whole tool.

Most RC screws are hex, but some use Phillips or slotted heads. A small set covering all three means you are ready for any fastener on the car.