A CURT 5th wheel wedge is a simple but reliable way to allow a CURT 5th wheel hitch to be used with a rotating 5th wheel pin box. A pin box mounts on top of the 5th wheel head and provides a new pivot point for the kingpin and wider turn radius for the 5th wheel trailer. To keep the pin box from swiveling in its 5th wheel mounting location, a 5th wheel wedge inserts into the hitch head, locking the pin box into place. This 5th wheel wedge is designed to fit the CURT E16 5th wheel and accommodates the Sidewinder* pin box. It comes with all necessary hardware and features a durable carbide finish for rust-resistance.