Extra Hard Steel Pinion Gear 5mm Bore Mod0.8 21T (RRP8721)

Extra-Hard Steel Pinion Gear, 5mm bore, 0.8 module, 21 teeth. This high-carbon steel pinion is built for brushless RC car motors, delivering long-lasting durability and precise gear mesh under high-speed power.

Includes one 4mm set screw and is designed for a 5mm motor shaft; a 2mm Allen wrench (not included) fits the set screw. For 1/8" shaft motors, a reducer sleeve is required. Note that 32-pitch and 0.8-module gears can be used together with no adverse effects, though the 0.8-module gear has a slightly larger outside diameter per tooth (about 0.00027 inches).