Roller Chain Sprocket Bore Diameter 2 in For Chain Pitch 1 1/4 in For Number of Strands Single Hub Type One Side Material Steel Maximum Bore Diameter 2 in Number of Teeth 18 Outside Diameter 7.84 in Pitch Diameter 7.199 in Bore Type Fixed Chain Number 100 Finish Black Oxide Hub Diameter 4 1/2 in Hub Projection 1.058 in Includes Set Screws Keyway Yes Keyway Width 1/2 in Length through Bore 1 3/4 in Number of Set Screws 2