Shimano Ultegra SM-RT800 Center-lock Disc Rotors

FEATURES:

• Freeza technology, 3-layer structure with aluminum core and stainless steel outer layers and additional aluminum cooling fins reduces rotor surface temperature approximately 150 degrees Celsius compared to all-steel rotors
• Aluminum spider
• Includes standard type rotor lockring
• Requires external-type rotor lockring when installing onto 15/20mm axle hub