New 72 tooth #35 chain zinc plated steel sprocket with 6 lightning holes. The 4 mounting holes are drilled for 3/8" bolts at 2" centers. Center hole is drilled 1-3/8" so bearing fits inside to better line up the rear axle. Can be used on most 6" wheels with that bolt pattern. overall height is 8-3/4". Perfect for Ruttman, lil Indian, and many others. Install on your every day rider or restoration.