These 6mm bore, 32 pitch pinion gears attach directly to all of our 6mm shaft gearmotors. Simply slide them on and tighten the 10-32 set screw. These gears have a 20 degree pressure angle. Manufactured from hardened brass gear stock. Compatible with our Standard Spur Gear Motors, Premium Gear Motors and HD Planetary Gear Motors. The set screw requires a 3/32” Hex Key (sold separately