This is a BikeMaster steel rear sprocket, black, part number: 965327. Fitment is I know at the moment, I am looking into figuring it out. I believe it may be for Honda or Harley-Davidson sprocket conversion for belts. Below are the dimensions:

Bolts Pattern: 4 x 4.325” (4 x 110 mm)

Hub Diameter (Sprocket I.D.): 3.125” (80 mm)

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