Sprocket Bore Diameter 3/8 in For Chain Pitch 1/4 in For Number of Strands Single Hub Type One Side Material Steel Maximum Bore Diameter 1 in Number of Teeth 30 Outside Diameter 2.529 in Pitch Diameter 2.392 in Bore Type Plain Chain Number 25 Finish Black Oxide For Pitch Type Single Pitch Hub Diameter 1 1/2 in Hub Projection 0.515 in Includes Set Screws Keyway Yes Keyway Depth 3/64 in Keyway Width 3/32 in Length through Bore 5/8 in Material Grade 1045