This Robinson Racing Products 17-tooth pinion gear is cut to the 48-pitch standard and features a 5mm bore sized for common brushless and brushed motor shafts. It is machined from hardened metal for increased wear resistance over standard pinions, making it a durable upgrade or factory replacement for a wide range of 1:10 and similar scale vehicles. A set screw is included for securing the gear to the motor shaft. Features: 17-tooth 48-pitch pinion 5mm bore fits common motor shafts Hardened metal construction for extended wear life Includes set screw 7/7/26 cs