Roller Chain Sprocket Bore Diameter 1/2 in For Chain Pitch 1/4 in For Number of Strands Single Hub Type One Side Material Steel Maximum Bore Diameter 1/2 in Number of Teeth 30 Outside Diameter 2.529 in Pitch Diameter 2.392 in Bore Type Fixed Chain Number 25 Finish Black Oxide Hub Diameter 1 1/2 in Hub Projection 0.515 in Includes Set Screws Keyway No Keyway Depth Not Applicable Keyway Width Not Applicable Length through Bore 5/8 in Number of Set Screws 2