XD-15 is the ultimate ceramic hybrid bearing. When nothing but the fastest, most durable, AND most corrosion-proof will do, XD-15 High Nitrogen Steel, paired with Silicon Nitride balls can't be beat. The Grade 3 made-in-USA ceramic ball bearings are 7 times harder than steel. XD-15 nitrogen steel alloy has proven it's superior corrosion resistance and longevity in aerospace applications. It's tough, long lasting, and the THE MOST corrosion resistant race material available. ALL OTHER ceramic hybrid bearings are a trade off.

Fitting a SRAM DUB 29mm spindle into a "BB92" (41mm ID) shell does not leave much room for the bearings. By making the outer race of these bearings into the "cup" and adding a second row of ball bearings, a very strong and reliable bottom bracket option has been achieved.

Please note that this adapter bottom bracket is designed for use with BB92 bottom bracket shells with a press-fit ID of 41mm in conjunction with a SRAM DUB MTB crankset. THIS WILL ALSO WORK with a BB86 road bottom bracket shell when paired with a SRAM DUB road crankset. The DUB crank spindles may at first glance appear to have 30mm diameters. In fact they, have a 28.99mm proprietary spec. We like to keep things real and call this a nominal 29mm crank spindle OD.