Hope pf46 press fit 30mm sram bottom bracket our press fit bottom brackets feature high quality sealed cartridge bearings providing a solution to the press fit bottom bracket minefield features pf bottom brackets are designed to fit bikes with a threadless bottom bracket cup the bearing cups thread into a centre tube to give a very secure safe fit cups pressed in and held in place by a screw in centre tube to prevent slipping and play bearings steel bb shell 46mm bb shell frame width 80mm