Avid Post Mount Brake Adapter Manufacturer Warranty: 2 years Material: aluminum, steel Attachment Type: 140mm rear post mount, 160mm front post mount Compatibility: [10mm] 10S fits 170mm Front Rotors, [20mm] 20S/20P fits 180mm Front and 160mm Rear Rotors, [30mm] 30P fits 170mm Rear Rotors, [40mm] 40P fits 170mm Rear Rotors