-Works quality RK racing chain and front and rear sprockets in one convenient package

- All RK chains feature high carbon alloy steel solid rollers, bushings and pins

- Heat-treated and pre-stressed for maximum wear life and performance

- Kits include 520KZU ultraring chain with ultrathin O-ring, the Baja-winning 520SMO, MZX XW-ring racing chains or quality TZ or KZ series non-O-ring chain

- Rear sprockets made of 7075 T-6 aluminum, unless noted; fronts made of case-hardened steel.