The Hard Case Bolt Lock-R assembly is designed to keep sprocket/pulley bolts from loosening, backing out, and causing costly damage or worse. The pulley/sprocket bolts are held in place by the Bolt Lock-R Keys. Bolt Lock-R does not require any additional modifications to your final drive or rear hub. Bolt Lock-R is a direct bolt on product. Bolt Lock-R does not include pulley to wheel bolts. Bolt Lock-R is used for hex head bolts (will not work with ARP hardware). Follow factory torque specs for your application.