PBI 25-Tooth .750 Offset Transmission Sprocket For Harley Big Twin Features CNC-machined from a premium nickel, chromoly steel (8620), case hardened and finished with an electroless nickel plating for corrosion/wear resistance and lubricity Sprockets are drilled and tapped to accommodate late model lock plate, available separately Offset measurement is taken from the face that rests against the main shaft bearing to the inside of the teeth for total offset description For use with .530 pitch chain 25-tooth sprocket