This is a 1/4" (.250) thick "R" Drive axle plate that can be used to check endplay on an aluminum hub. The steel plate would be bolted to the aluminum hub using the nuts that hold the drive axle in place. This bracket is Zinc plated to prevent rusting.
Please note that you will need two of these plates to install one on each side of hub to match up to the dial indicator magnets. The hub bolt pattern is drilled to fit hubs with 5/8" and/or 3/4" drive axle flange studs with 7" on center with 8 studs.
You will also need a (1) One extension tip for the dial indicator so the probe will reach the face of the spindle when using Aluminum hubs.
