This billet aluminum swing arm is lighter and sturdier than stock. It increases driving stability and improves control. Also features upgraded axle and bearings. Easy to install with no permanent modifications of the bike but must be installed with a radial brake caliper such as our PM Radial mount 4-piston calipers ZPN 743172 or 743082 and Vity's rear brake caliper bracket. Swing arm and caliper brackets are CNC machined from billet aluminum and are raw aluminum or have an anodized finish. To allow multiple color combinations the swing arm, caliper bracket and brake caliper must be ordered separately.