T47-External, Threaded, Ceramic Hybrid, XD-15, Angular Contact Bearing, Bottom Bracket for T47 Framesets An Enduro Bearings exclusive, our XD-15 Pro BBs feature XD-15 15 Angular Contact cartridge bearings pressed into precision machined aluminum T47 cups that simply thread directly into the BB shell. Utilizing the same XD-15 steel as our XD-15 Corsa bearing, Enduro XD-15 Pro bearings offer a 15 angular contact sealed bearing in a standard-sized cartridge. XD-15 Pro bearings feature deep-groove raceways allowing for maximum sized Grade 3 Silicon Nitride ceramic balls for for increased contact area and improved performance and longevity. Enduro XD-15 bottom brackets are manufactured to the highest standards at the Enduro Bearings production facility in California, USA. Enduro XD-15 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. We are so confident in XD-15, that we offer an unlimited lifetime bearing and race warranty. The most impressive feature of these 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, while the other ceramic-hybrid options will only get slower. Shell Fitment: T47 Bearings: XD15 Pro Seal Type: LLB Grease Kluber CRC Marine Grease Axle Size: 24mm, 29MM (DUB), 30mm Warranty: Limited Lifetime Enduro Reference Number: 24mm - BKC-0779 / 29mm (DUB) - BKC-0771 / 30mm - BKC-0776