Sprocket Bore Diameter 1 5/8 in For Chain Pitch 1 in For Number of Strands Single Hub Type One Side Material Steel Maximum Bore Diameter 1 5/8 in Number of Teeth 30 Outside Diameter 10.11 in Pitch Diameter 9.567 in Bore Type Fixed Chain Number 80 Finish Black Oxide Hub Diameter 4 3/4 in Hub Projection 1.425 in Includes Set Screws Keyway Yes Keyway Depth 3/16 in Keyway Width 3/8 in Length through Bore 2 in Number of Set Screws 2