Black MTB Cassete 8/9/10/11/12 Speed 40/42/46/50/50T K7 8/9/10/11/12v Bicycle Freewheel Bicycle Sprocket for Shimano/SRAM. Material Steel (40T, 42T) / Steel + Aluminum Alloy (46T, 50T, 52T). Material: Steel (40T, 42T) / Steel + Aluminum Alloy (46T, 50T, 52T).
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