Solid rollers. Shot-peened parts. High cylindrical and roundness accuracy. Exacting tolerances provide low friction. Pre-stretched. Extended riveted bushing "Anti-Kink" design. Special alloy steel. Average tensile strength of 4,200lbs. Always replace your chain with the same size, grade and type of chain as originally equipped by the manufacturer. Be sure to use a rivet type connecting link if the original chain is an endless chain.