Roller Chain Sprocket; 1-1/4" Bore; 50 Chain; 12 Teeth; 1 Row of Teeth; No Hardened Teeth; 2.708" Outside Diameter; 2.415" Pitch Diameter; B-Hub One Side; Finished Bore Mount; No Bushing; 5/8" Chain Pitch; ANSI Roller Chain; Keyway; Steel Material