Curt Manufacturing 45521 Towing Wiring Fits trailer hitches with a 1 1/4" x 1 1/4" receiver tube opening Equipped with a 3/4" hole to accept a trailer ball shank 2 5/8" rise or 3 1/4" drop for precise trailer leveling Shank constructed from solid steel for optimum strength CNC-formed, robotically welded and mechanically descaled for a perfect fit