Sprocket Bore Diameter 1/2 in For Chain Pitch 3/8 in For Number of Strands Single Hub Type One Side Material Steel Maximum Bore Diameter 1 1/4 in Number of Teeth 19 Outside Diameter 2.47 in Pitch Diameter 2.279 in Bore Type Plain Chain Number 35 Finish Black Oxide For Pitch Type Single Pitch Hub Diameter 1 7/8 in Hub Projection 0.582 in Includes Set Screws Keyway Yes Keyway Depth 1/16 in Keyway Width 1/8 in Length through Bore 3/4 in Material Grade 1045