This stainless steel Clam Shell converts most 2 Inch tow balls into a 2-5/16 Inch tow ball and can be used on most bumper pull systems. With its free rotation design, this must-have accessory has been created to have a free rotation around the tow ball which will mini-mize friction wear and increase the longevity of your Clam Shell. The conservative design is meant to minimize weight and increase the ease of use. You can store this accessory in your glove box or under the seat, eliminating the need of heavy, awkward additional tow balls.