Campagnolo CENTAUR ULTRA-Drive 11 speed Cassette w/11t lockring. Stock in retail box. Never mounted or used. Centaur sprockets use the Ultra-Drive system and are the fruit of continuous research and development to improve our products. The Ultra-Drive system makes shifting more precise and fluid, especially thanks to the careful machining and treatments that the sprocket teeth have undergone. The special sprockets pattern interfaces perfectly with the rest of the drivetrain components, especially the chain and chainrings, thus bringing performance to levels of outstanding excellence. Compatible with ALL Campagnolo 11 speed drivetrains. Largest 2 cogs 1 piece. Smallest 8 cogs individual with spacers. Supplied with 11t lockring. Our goal is to have happy repeat customers and lots of great feedback.