PF30 Outboard ZERØ Ceramic BB for 24mm Cranks (Shimano) - Black.Thread together bottom bracket for frames using the PF30 bottom bracket standard.Two machined aluminum cups thread together keeping the bottom bracket stable in the frame, increasing bearing life, and simplifying maintenance.This means no more creaking, smoother operation, longer bearing life, and really quick bearing replacement.Specifically designed for installing 24.00mm spindle diameter cranks (Shimano, Etc.) in PF30 (46mm ID BB shell) frames without the need for any adapters..Bottom Bracket Includes:BB Cups with bearings.2 - Silicone dust seals.2 - 0.5mm crank spindle spacers.2 - 1.0mm crank spindle spacers.Bearings:Enduro ZERØ Ceramic.Color:Black.Bottom Bracket/Frame Interface:PF30, Specialized Carbon OSBB*.Bottom Bracket Shell Width:61mm* - 73mm.Bottom Bracket Shell I.D.:46mm.Over Bearing Width:90.5mm in 68mm wide shell.Crank Spindle Diameter:24.00mm.Tool Pattern:44mm, 16-notch.Weight:156g.Packaged for retail display.*Notes:Specialized Carbon OSBB frames with a 61mm shell width need additional cup spacers.BB cups produced after July 2018 do not use o-rings.Over Bearing Width Dimensions include supplied silicone dust shields.Compatible with the following Bottom Bracket Standards (46mm BB shell inner diameter):PF30.Specialized Carbon OSBB.May need additional cup spacers if BB shell width is 61mm.Compatible with 24.00mm spindle diameter cranksets.*