External BSA, English threaded bottom brackets featuring a unique self-cleaning hybrid ceramic bearing system for the ultimate in strength and durability Cartridge bearing system that feature a single ceramic ball with the remaining being steel with steel races, combining the strength of steel the bearing life of ceramic The single ceramic ball bearing pulverizes contaminates, reworks and polishes the steel races with every rotation Offered in 24mm Shimano, FSA, Race Face, etc with an expandable sleeve that fits 68mm to 100mm shells Offered in 24mm Shimano, FSA, Race Face, etc with an expandable sleeve that fits 68mm to 100mm shells Scramjet BSA threaded BB, 24mm, silver Bearings include a 5 year warranty