TheDT Swiss Centerlock Adapterallows ISO 6-bolt rotors to be quickly and easily fitted to the splines on a centerlock brake rotor mount. With the lockring's external tool splines, the internal diameter of the adapter is increased, allowing for use on hubs with all common axle standards: quick release, 12mm, 15mm, and 20mm. These high quality adapters are manufactured in Switzerland by DT Swiss.