Shimano SLX RT70 M7000 Center Lock Rotor The SM-RT70 Ice-Tech rotors have a sandwich structure of an aluminium core embedded in 2 stainless steel layers. The higher heat dissipation of the aluminium helps to reduce the surface temperature of the rotor by around 100 degrees Celsius. Optional Ice-Tech brake pads with aluminium cooling fins can reduce the brake pad surface temperature by another 50 degrees. The result is high stopping power and practically no signs of fading! They feature a new design with refined shaping over the RT68 rotor. An aluminium lockring is a further improvement over the older steel version making the package more light weight. Centerlock Disc not compatible with IS2000 disc rotor mount (6 hole system) The 180/203mm disc requires a special adapter. Please do not exceed the disc specifications of your fork/frame.