ProTaper Pro Series Forged 520 Slim O-Ring Chain 120LUtilizing a newly developed manufacturing technique never before seen in the offroad chain market, ProTaper Pro Series chains feature innovative forged pin collars that have been seamlessly incorporated into the outer chain plate. By cold forging pin collars to encase the thermally refined, chromium carbide layered pins, outer chain plate thickness can be slimmed to reduce weight while increasing tensile strength. Featuring Slim O Ring Technology,