The new SRAM DUB crank standard, built on a 28. 99 spindle, allows for a more contamination resistant BB design, while retaining the ultra-efficient & long-lasting qualities CeramicSpeed Bottom Brackets are known for. With an integrated dust cover for all models, a snug & secure fit that also fully protects the face of the bearing delivers exceptional performance without any sacrifices. CeramicSpeed hand-built bearings carry the load from crank to frame with un-paralleled durability & efficiency.