Regina Chain 520 ZRE Z-Ring Chain - 120 Links - Gold 135ZRE/1008New, high performance ZR chains with new patented Z44 seal Z ring sections Z ring flexes when assembled, creating a spring effect that guarantees seal will not diminish over time Z ring section also provides enhanced chain flexibility Features high alloy steel plates and pins, solid bushings and rollers and shot peened plates, pins and rollers Pre stretched to enhance performance Clip type and rivet type links included