Shimano xtsaint rt81 ice tech cl disc rotorsm rt81 ice tec rotors give excellent performance made from a stainless steelalloy 3 layer sandwich construction that manages heat while riding the clad steelalloysteel rotor construction allows heat generated from braking to radiate quickly through the aluminium core achieving surface temperature drops of around 50c when used with ice tec pads surface temperatures can drop from around 400 to 300c this provides great improvements in performance