T47-Threaded, Ceramic Hybrid, XD-15, Angular Contact Bearing, Bottom Bracket for T47 Framesets. Enduro's top of the line BB bearing kit, we couple our XD-15 Ceramic-Hybrid, ABEC-5 bearings along with all of the necessary seals and spacers to complete a precise, professional installation. An Enduro Bearings exclusive, our XD-15 Ceramic-Hybrid bearings combine corrosion-proof, cryogenically treated nitrogen steel races with Silicon Nitride Grade 3 ceramic balls in a proprietary process that results in the ultimate high performance bearing setup. The deep-groove design raceways allow for maximum sized Grade 3 Silicon Nitride ceramic balls for for increased contact area and improved performance and longevity. 90% fill Kluber NBU52 grease only runs better and smoother with time and is highly resistant to being washed out. It is engineered to stick to the balls and continually be pulled back into the ball path where it is needed. The most impressive feature of XD-15 bearings is, unlike other bearings, they only get better with use. As the bearings wear-in, the balls actually make the races even smoother. So when compared to other ceramic-hybrid bearings on the market that claim speed and power advantages on day one, Enduro XD-15 bearings not only provide the same initial advantages on day one, but will get even faster and smoother with time and use. We are so sure that you will agree, that we offer an unlimited lifetime bearing and race warranty. Shell Fitment: T47 Internal Bearing Bearings: XD-15 Ceramic Seal Type: LLB Grease Kluber NBU52 Grease Axle Size: 24mm, 29MM (DUB), 30mm Warranty: Unlimited Lifetime Enduro Reference Number: 24mm - BKC-0796 / 29mm (DUB) - BKC-0799 / 30mm - BKC-0791