These GT2 pulleys will fit on any NEMA 17 motor with a 5mm shaft. They will work with any standard GT2 belt, and the large 20-tooth profile gives them a strong and reliable grip.
Teeth Number :20 teeth
Outside Diameter (OD):16mm
Bore of Timing pulley:5mm
Fit to : Timing belt with 6mm Width
1X GT2 Timing Pulley 5MM 20 Teeth Pulley for Reprap 3D Printer