ceramicspeed-shimano-11-speed-pulley-wheels-coated-alloy-limited-edition-blue
ceramicspeed-shimano-11-speed-pulley-wheels-coated-alloy-limited-edition-blue, 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