TRAP Timing Belt Pulley Bore Diameter 3/4 in For Belt Series H For Belt Width 1 in For Use With L Belts Material Ductile Iron Maximum Bore Diameter Not Applicable Number of Teeth 21 Outside Diameter 3.574 in Pitch 0.5 in Pitch Diameter 3.342 in Bore Type Plain Face Width 1.313 in Features Built for High-Torque Low-Speed Applications Outperforms Industry Standards Superb Flexibility Finish Black Oxide For Belt Trade Size H Hub Diameter 2 5/8 in Hub Projection 13/16 in