ACB 6808 CC SXD - 1-1/2" XD15 angular contact bearing for the headset (40mm x 52mm x 6.5mm; 36 x 45 degrees), angular contact bearing for the inner headset with 440C stainless steel balls in conjunction with XD15 bushings for lifelong corrosion resistance. Newly developed by Enduro, these XD15 bearings are nearly identical to our XD15 ceramic hybrid bearings in terms of performance and corrosion resistance, but are better suited for the more abusive application of the headset. The mechanical properties of the XD15 stainless steel balls provide a higher level of shock resistance than ceramic balls for headsets. The XD15 ball and bushing bearings tested by Enduro have been used in saltwater for months without any corrosion; there is simply nothing comparable on the market. This bearing size is also known in the bicycle industry under the following part numbers: HD 1404K, BAA0006K, MR-127, MR-196, MH-P25K, BAA1132. Enduro's range of angular contact bearings for headsets starts with rings made of black oxidized chrome steel, progresses to 440C stainless steel, and culminates with XD15 stainless steel for aerospace (rings and balls) with a lifetime warranty. They are always constructed with the largest possible balls, feature double lip seals that sit in a micro groove (labyrinth), and are filled 90% with waterproof high-pressure grease to provide ultimate protection against sweat and the elements. The Enduro angular contact bearings (A/C) are designed so that all balls engage evenly, distributing the load over a larger area, thereby minimizing wear and maximizing lifespan.