This is the Shimano XT RT86 Icetech Disc Brake Rotor for 6-bolt compatible wheels. The 3-layer structure with aluminum core and two stainless steel outer layers reduces rotor surface temperature by approximately 100 degrees Celsius compared to all-steel rotors.
Features:
6-bolt Ice-Tech Rotor
Aluminum core construction
Lowers operating temperature
Resists power fade
Increases pad life
ICE TECHNOLOGY Rotor: Cooling technology for consistent performance.