RK Racing Chain GB520EXW-124 124-Links Gold XW-Ring Chain with Connecting Link Sealed XW-ring chain features heat treated hi-carbon alloy steel components with seamless rollers and shouldered bushings XW-ring is made of an advanced Nitrile Butadiene composite featuring three contact lips and two convex outer stabilizers. This means three lubrication pools to protect against high speed abrasion, extreme heat build up, torsional flex and loss of lubricant XW-Ring chains are the best high-speed, extreme heat performance chains available today The XW-ring provides the user with a 50% longer wear life than basic o-ring chains 5GB20EXW has a maximum tensile strength rated at 8500 foot pounds and is suitable up to 400cc street bikes and 750cc off-road bikes/ATV's