SPEDAO 10-50T 11-50T 12Speed Bicycle Cassette 12v MTB Bike Freeewheel 12S Mountain Sprocket XD HG Cassette 12V K7 for SX NX GX. ULT 10-50T XD Compatible: Fit for Sram XD. PRO 10-50T XD Exclusive patent integrated ring gear.
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