These rotors have a stainless steel braking surface riveted to an aluminium central carrier. As well as offering a significant weight saving, they also allow the rotors to expand or contract with changes in temperature. The rotors are available in 140, 160, 180, 183, 185, 200, 203 and 205mm in the full range of colours. For further weight savings we also have the lightweight floating rotor available from the Race X2 brake as an after market part. Only available in 160 or 140mm sizes and with a black centre, these lightweight rotors are only 1.8mm thick as opposed to the standard 2mm - which gives incredible weights: 160mm is 78g and the 140mm is just 64g! Add the Ti bolt kit to reduce weight even further!