BBB Pair of ALUBOYS Rollers C ramic 9-10-11 Speeds

7075 aluminum derailleur rollers. Extra rigid for a more precise shift. High quality annular ceramic bearing. Super flexible and resistant.Compatible with Shimano 9, 10 and 11-speed (except RD-7900 and 7970) / Mega Range, SRAM X0 / X9 / X7, Apex, Rival, Force and Red (> 2011) and Campagnolo 11-speed.