SX SXF EXC EXCF EXC TPI, XC XCF XCW 125 200 250 300 350 450 500 505 525. Supersprox Rear Alloy Motocross Sprockets for MX & Enduro Bikes - Supersprox Motocross Sprockets. Supersprox Alloy Sprockets are CNC Machined from a tough 7075-T6 aerospace aluminium and are the best and the lightest aluminium sprockets in the world.
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