The Star screwdriver bits fit Torx screws and unlike the other Torx screwdriver bits, have the signature Chapman snap ring groove and knurl end.

Torx screws are commonly found on the following,  automobiles & motorcycles (GM especially), bicycle brake systems (disc brakes), computer systems & hard disk drives, consumer appliances & electronics, CNC machines, appliances, Jeep Wranglers, firearm scopes and mounts, dental, medical, x-ray, electronics, drones and knives.The Star Bits are also in the Master Kit 5575