Target Gender: Boys KAWADA Carbide Dura Pinion Gear is an ultra-high-precision gear machined from lightweight duralumin that is hard-plated!! KAWADA is the first in the industry to successfully apply hard plating to duralumin. By applying hard plating, we have succeeded in securing a surface hardness of HV600 and dramatically improving durability!! Carbide Dura pinion gears have high quality precision in both tooth tip circle and pitch circle. Clears standards!! Motor drive is reliably transmitted to the spur gear without loss. For shaft diameter 3.175mm (1/8 inch). <Set contents> Pinion gear: 1 piece M3X3 immobilis: 1 piece (from Discovery Japan Mall)