BUCKLOS BSA Bottom Bracket characterize cold-forged machined aluminum alloy cups, dual-labyrinth bearing covers and precision sealed bearings, weight about 74.7g.Fit frames with 68/73mm bottom bracket shells,BC1.37-inch*24T L/R Threaded Connection design enhance lateral stability to avoid creaking sound. Bottom Bracket ： Brand: BUCKLOS Size: BC1.37-inch*24T L/R( threaded) Spindle/Bearing inner diameter: 29mm Fit BB shell width: 68/73mm Weight about: 74.7g. Materials:Aluminum alloy Intended Use: road bike Shell width: Fit frames with 68/73mm bottom bracket shells Thread: BC1.37-inch*24T L/R Threaded Connection design enhance lateral stability to avoid creaking sound. Material: BUCKLOS BSA Bottom Bracket characterize cold-forged machined aluminum alloy cups, dual-labyrinth bearing covers a.