Made for the serious motocross racer, 520MXZ4 is available in our distinctive gold or metal racing finish. MXZ chains feature chromoly steel construction with seamless rollers and bushings, and oversized special alloy pins for added strength. All components are heat-treated using RK's exclusive HIT (Heat Induction Transfer) process. 520MXZ4 is the lightest and strongest Motocross chain available today! 520MXZ4 chain is ideal for the professional level racers 125cc to 500cc Open Class racing.