Roller Chain Sprocket, Bore Diameter 1 in, For Chain Pitch 1/2 in, For Number of Strands Single, Hub Type One Side, Material Steel, Maximum Bore Diameter 1 in, Number of Teeth 48, Outside Diameter 7.93 in, Pitch Diameter 7.645 in, Bore Type Fixed, Chain Number 40, Finish Black Oxide, Hub Diameter 3 1/2 in, Hub Projection 0.841 in, Includes Set Screws, Keyway Yes, Keyway Width 1/4 in, Length through Bore 1 1/8 in, Number of Set Screws 2