11T. Composite material from EMS Swiss featuring a 40% fiberglass blend. Special tooth profile designed for quick shifting performance. Includes compatible bushings for various shifting systems. Compatible with Shimano 9-, 10-, and 11-speed/MegaRange, SRAM X9/X7/X0 (2011 and later), Apex, Rival, Force, and Red (2011 and later), as well as Campagnolo 11-speed.