BB30 Bottom Bracket Bearings. Direct replacement for both bb30 and pf30 press fit bearings. Bearing dimensions: (30 x 42 x 7mm) 6806-2RS BB 30 hybrid ceramic ball bearing rebuild kit. You will receive two ceramic hybrid bb30 bearings. These also replace pf30 press fit bottom brackets. Model numbers - cross ref: (6806-2rs) (6806-rs) (bb30). Bearing dimensions: (30 x 42 x 7mm) - bearing material: stainless steel races, ceramic balls, stainless steel cages, nbr close contact seals. Fits: press fit pf30 & bb30 bottom bracket frames. Weight just 45 grams.