Roller Chain Sprocket Bore Diameter 1 7/16 in For Chain Pitch 3/4 in For Number of Strands Single Hub Type One Side Material Steel Maximum Bore Diameter 1 7/16 in Number of Teeth 25 Outside Diameter 6.39 in Pitch Diameter 5.984 in Bore Type Fixed Chain Number 60 Finish Black Oxide Hub Diameter 4 in Hub Projection 0.791 in Includes Set Screws Keyway Yes Keyway Width 3/8 in Length through Bore 1 1/4 in Number of Set Screws 2