Xtr fully bled trail brakes are performance optimized servo wave systems with full adjustability on the fly front fully bled lever and calliper comes without adapters or rotors giving you the freedom to customise and suit your bike recommended for use with ice tech centre lock rotors for optimum braking performance in a choice of 160 180 and 203 mm short stroke servo wave mechanism with sil tec roller for a quick smooth pad engagement and more power for aggressive riding free stroke adjustment