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 3-12V Standard Gearmotors, Precision Gearmotors and HD Planetary Gearmotors.