Renthal R3-3 chains are specially developed utilising Renthal's SRS (self-regulating seals) technology to increase longevity. The SRS is pre-loaded during assembly, creating a spring effect. As a chain wears, conventional O-rings and X-rings loosen their seal whereas the SRS has the inherent ability to regulate a constant sealing pressure against the side plates throughout the life of the chain, increasing the service life of the chain.