This Robinson Racing Products 23-tooth pinion gear is cut to 48 pitch and features a 5mm bore, making it a direct fit for a wide range of 1:10 scale electric vehicles running 48P drivetrains. The 'Hard Machined' designation indicates a hardened metal construction for increased durability over standard pinions. A set screw is included for securing the gear to the motor shaft. Features: 48 pitch, 23 tooth count 5mm bore fits common 1:10 scale motors Hardened metal construction Includes set screw 7/7/26 cs