420 Chain & Sprocket Kit (37T Rear / 17T Front). Complete Drive Assembly: Includes 420 Chain, 37T Rear Sprocket, 17T Front Sprocket, and fixing hardware. Rear Sprocket 420 37T (155mm). Wide Compatibility: Specifically designed for 50cc to 125cc Dirt Pit Bikes, Mini Bikes, ATVs, and Go Karts.
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