Hub shells are produced from bars of cold finished proprietary 6000 series aluminum produced in their designated Midwestern U.S. mill. The tight grain structure of the cold finished alloy used in the hub shells provides two special advantages. The first is to provide a lifetime warranty on the hub shell against breakage due to this material and workmanship. The other is to produce a hub shell capable of their trademark hand polished finish. This material enables them to offer a high gloss black anodize finish as a custom option on most hub models