Open Primary Belt Drive Lock Up Clutch Kit For Harley Shovelhead BDL 77316. Centrifugal force allows the actuater arms to move outward, which applies extra pressure against the pressure plate and clutch springs for positive engagement with no clutch slippage. Gives you the advantage of using the lighter pull 6 clutch spring set with no clutch slippage at hard throttles. Works well on any size engine. Manufactured from hard anodized CNC machined billet aluminum.DOES NOT INLCUDE PULLEY, SHOWN FOR REFERENCE Lock up clutch kit for BDL clutches. Fits BDL 8mm belt drives with dome style BDL pressure plate.