This kit consistes of two 4 inch square plates with heavy 1/2 inch nuts welded in the centers to secure the stand to the trailer, when the trailer floor might need added support. The kit comes with 2 plates with wood screws for mounting the plates to the underside of trailer and two 1/2 inch bolts X 2 inches long for mounting either the wheel chock or the optional transport bar from the top side. Note; This provides the ultimate in mounting strength. these plates are powder coated with the same epoxy finish as the Wheeldock unit.