Roller Chain Sprocket; 1" Bore; 50 Chain; 57 Teeth; 1 Row of Teeth; No Hardened Teeth; 11-45/64" Outside Diameter; 11.346" Pitch Diameter; B-Hub One Side; Finished Bore Mount; No Bushing; 5/8" Chain Pitch; ANSI Roller Chain; Keyway; Steel Material