Attack Black Star RKP (Reverse Kingpin) Trucks are the first trucks to come with multiple configurations to dial in your ride. Each truck comes complete with three (3) green Abec 11 Reflex urethane bushings (90a durometer) and a harder black .100” bushing spacer. The standard configuration uses the tall (.750”) bushing on the bottom (boardside) and the medium (.650”) bushing on top (roadside) and no bushing spacer. Using the taller two bushings allows for a greater range of motion when turning, perfect for hard carving and high speed cornering. To restrict the amount of lean, put the shortest bushing on top, the medium bushing on the bottom, and the bushing spacer between the bottom cup washer and the baseplate. This setup is used for better sliding and drift control when freeriding and also helps you to avoid wheel-bite. Attack hangers and baseplates are fully compatible with the precision CNC machined hangers and baseplates from the Liquid Truck Company.