BikeMaster 520BMOR 120 Link Chain Up-graded Bike Master O-ring chain offers not only the industry&rsquo;s best value-price but also the highest durability Component designs optimized with computer analysis provide higher tensile strength Specially controlled heat treatment means tougher material Reinforced rollers offers higher impact resistance and longer durability &rsquo;&rsquo;Round rivet head&rsquo;&rsquo; offers superior rigidity over 2 or 4-point (quad-staked) riveting