PCGT Timing Belt Pulley For Belt Series Poly Chain GT Carbon For Belt Width 21 mm For Bushing Size 1108 For Bushing Type Taper Lock For Use With Poly Chain GT Carbon Belts Material Steel Maximum Bore Diameter 1 1/8 in Minimum Bore Diameter 1/2 in Number of Teeth 28 Outside Diameter 3.15 in Pitch 8 mm Pitch Diameter 2.807 in Face Width 1.203 in Features Built for High-Torque Low-Speed Applications Outperforms Industry Standards Superb Flexibility Finish Black Oxide