... . Gear Hardness 53 Shaner factory is professional manufacturer of power tools, and matched spare parts: armatures, stators, aluminium casting, gears ... and carbon brush.Power Tools Gears and Carbon Brush:1. 100% suitable for BOSCH 20S ... , Gear is 20CrMnTi4. Gear hardness is 53, as our tools all parts are the same hardness: armature shaft, gear, spindle. Power ...