SPEDAO 10-50T 11-50 12Speed Bicycle Cassette 12v MTB Bike Freeewheel 12S Mountain Sprocket XD HG Cassette 12V K7 for SX NX GX. Aviation Aluminium 7075 (50T). Type :MTB Bike Freewheel. ULT 10-50T XD Compatible with XD freehubs.
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