This GT2 Timing Pulley is perfect for your 3D printing and other CNC applications. It has 20 teeth, is suitable for a 10mm GT2 Timing belt, and couples to a Nema 23 stepper motor shaft with its 6.35mm bore and two M4 grub screws. Technical Specifications:
Tooth Profile: GT2                      
Belt Compatibility: GT2 : 10mm wide
No. of Teeth: 20
The pitch of Profile: 2mm
Material: Aluminium
Bore: 6.35mm
Grub Screw: 2 x M3