100BS12H X 2 Sprocket - 1 1/4" Pitch - 12 Teeth - 2" Finished Bore Includes Keyway & 2 Set Screws Hardened Teeth. Has recessed groove in hub for chain...100BS12H X 2 Sprocket - 1 1/4" Pitch - 12 Teeth - 2" Finished Bore Includes Keyway & 2 Set Screws Hardened Teeth. Has recessed groove in hub for chain...