This Robinson Racing Products pinion gear features an 18-tooth, 32-pitch (0.8 mod) design with a 5mm bore, built from blackened steel treated to an extra-hard finish for increased wear resistance. It is a factory replacement option compatible with a range of popular 1/10 and 1/8 scale electric platforms. The set includes the pinion gear and a set screw for shaft retention. Features: 18 tooth, 32 pitch (0.8 mod) 5mm bore for motor shaft fitment Extra-hard blackened steel construction Includes set screw 7/7/26 cs