Sprocket Bore Diameter 1/2 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 13 Outside Diameter 2.33 in Pitch Diameter 2.089 in Bore Type Plain Chain Number 41 Finish Black Oxide For Pitch Type Single Pitch Hub Diameter 1 9/16 in Hub Projection 0.648 in Includes Set Screws Keyway Yes Keyway Depth 1/16 in Keyway Width 1/8 in Length through Bore 7/8 in Material Grade 1045