Renthal R3-3 chains are specially developed utilizing Renthal's SRS technology for increased service life. Nitrile Self Regulating Seals (SRS™) retain a special vacuum-injected grease around the critical pin and bush area, which extends the life of the chain. Renthal's SRS (Self-Regulating Seals) system increases service life of chain. Comes pre-stretched for less adjustment during break-in. Rivet link has been changed to a hollow end to facilitate easier installation. High-carbon alloy steel pins, solid bushings and rollers, and shot peening of plates and rollers for increased fatigue resistance. Maximum machine performance: 68Nm and 55kW (50 lb/ft. and 73 bhp).