For serious racers concentrating on weight savings, XRAY\'s optional CNC-machined brake disk adapter is CNC-machined from tough 7076 T6 alu, and has been strategically lightened by 30% compared to the standard #334140 adapter. Rotating mass is reduced without sacrificing strength or durability. Includes factory-pressed pins (non-replaceable). - Lightweight brake disk adapter - Tough 7075 T6 aluminum - CNC-machined - Strategically lightened by 30%