Roller Chain Sprocket; 1-1/4" Bore; 80 Chain; 12 Teeth; 1 Row of Teeth; No Hardened Teeth; 4.332" Outside Diameter; 3.864" Pitch Diameter; B-Hub One Side; Finished Bore Mount; No Bushing; 1" Chain Pitch; ANSI Roller Chain; Keyway; Steel Material