The XX1 11-Speed Cassette is only compatible with wheels which use an XD driver (XX1 freehub body). It weighs 263 grams. SRAM XX1 XG-1199 11-Speed. Designed specifically for their single chainring MTB group, SRAM's XG-1199 cassette features an unprecedented 11-speed range from 10 to 42 teeth.
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