Deore XT grade RT-MT800 Ice Tech rotors give excellent performance made from a stainless steel / alloy 3-layer sandwich construction that manages heat while riding The clad steel / alloy / steel rotor construction allows heat generated from braking to radiate quickly through the aluminium core achieving surface temperature drops of around 50 deg C. When used with Ice Tech pads surface temperatures can drop from around 400 to 300 deg C, this provides great improvements in performance all round Ice Tech rotors achieve long pad life, less noise and less fade due to improved heat dispersion Using the proven Shimano Center Lock system for excellent rigidity and security with an easy set-up Rotor contact surface has been developed for excellent pad clearing and cooling which increases pad performance and life Large forged alloy spider supports rotor surface, increasing rigidity and reducing weight Comes complete with alloy lockring