Barnett Low Profile Lock-Up Clutch For Harley Big Twin Features Billet aluminum lock-up pressure plate designed to fit under the stock primary cover No need to change or modify your cover Three different coil spring sets included to provide a wide variety of spring pressure options allowing you to tune the clutch for stock to 200+ HP applications A steel inner hub is included to complete the unit Billet aluminum pressure plate, adjustable pressure arms increase spring pressure as rpm increases Can be run wet or dry