Roller Chain Sprocket; 1-1/4" Bore; 40 Chain; 38 Teeth; 1 Row of Teeth; No Hardened Teeth; 6.334" Outside Diameter; 6.055" Pitch Diameter; B-Hub One Side; Finished Bore Mount; No Bushing; 1/2" Chain Pitch; ANSI Roller Chain; Keyway; Steel Material