ceramicspeed-sram-1x11-pulley-wheels-for-sram-1x11-systems-alloy-black
ceramicspeed-sram-1x11-pulley-wheels-for-sram-1x11-systems-alloy-black, CeramicSpeed pulley wheels reduce friction, last 3-5 time longer than stock high-end pulleys, and are designed to work with less drag.Premium Grade 3 Silicon Nitride Ceramic ballsHand built in Denmark