This Robinson Racing Products pinion gear features a 5mm bore, 0.8 module (31.75 pitch) tooth profile, and a 22-tooth count. It is made from extra hard metal for increased wear resistance compared to standard pinions. A set screw is included for securing the gear to the motor shaft. This is a factory replacement pinion compatible with Traxxas platforms running 0.8 mod gearing. Features: 22-tooth count 5mm bore fits standard motor shafts 0.8 module / 31.75 pitch tooth profile Extra hard metal construction for increased durability Includes set screw 7/7/26 cs