2001 2002 Polaris Scrambler 500 2x4 Chain and Sprocket Sprocket Sprocket Set includes: 12T, 36T sprockets and 520-76L Non-O-Ring Chain All Race-Driven sprockets meet or exceed OEM specifications and use hardened S45C steel. Non-O-Ring chain doesn't have o-rings between the links so it is lighter, thinner and has less drag. Polaris Scrambler 500 2X4