Roller Chain Sprocket Bore Diameter 1 in For Chain Pitch 3/4 in For Number of Strands Double Hub Type One Side Material Steel Maximum Bore Diameter 1 in Number of Teeth 20 Outside Diameter 5.19 in Pitch Diameter 4.794 in Bore Type Fixed Chain Number 60-2 Finish Black Oxide Hub Diameter 3 3/4 in Hub Projection 0.784 in Includes Set Screws Keyway Yes Keyway Width 1/4 in Length through Bore 2 1/8 in