RK XSO Sealed Street Chains - RX SealsThe affordable, long lasting performance chain series. XSO chains offer less torsional friction and increased high-stress, high-speed performance at an affordable price. XSO chains provide 7 times longer wearlife compared to standard chains.520XSO RX-RING CHAIN- Tensile Strength: 11,250 Nm- Max CC Rating: 750cc Street, 750cc Off-road- Master Link Included: Clip/Rivet type- Weight: 1.56 kg (per 96 links)As part of their continuing quality improvement program, the RK Chain Factory has made a running production upgrade to their best selling XSO chain line. The XSO chains features RK's proprietary "RX-Ring" seal design and is offered in 428, 520, 525 & 530. All versions are available in a variety of colors. Viewed in cross-section, the RK "RX-Ring" has two contact lips and one lubrication pool versus the single seal point/pool design of a regular o-ring chain. RK's XSO chains offer quality, performance and unbeatable value, for all but the most demanding high performance application.Chain link configurations of 100 to 120 are available.