PF30 OSBB is the Specialized standard. The CeramicSpeed Shimano-compatible Bottom Bracket increases efficiency, durability, and reduces creaking. It also works with FSA and other 24mm diameter thru-axle cranks.The kit consists of two cups with CeramicSpeed Bearings installed. There are two variants. Both Standard and Coated Bearings feature super smooth CeramicSpeed Balls and hardened-steel races. The Coated have an additional feature: a 3-micron thick metallic layer over the races.The layer further smooths and hardens the steel, lowering drag and increasing life.In The Box1 bottom bracket with bearings installed.2 dust covers.10ml syringe of All Round Grease.Sticker sheet.The cups have extended sleeves and join with a center section on the PF30 OSBB reducing the likelihood of creaking and increase the reliability of the system.An average drag reduction of 75% compared to stock bottom brackets is the main feature of the CeramicSpeed Standard Bearings. That translates into frictional drag of 0.3-0.4 watts per set, which is the result of great design, hardened-steel races, and CeramicSpeed Balls that are 100% smoother and 15% harder than the ceramic competition. They also last longer.CeramicSpeed Coated Bearings last even longer and feature even lower drag. Life increases by 60% and drag drops by 50%.All Round Grease is installed in the CeramicSpeed Bearings. It can be replaced for lower drag TT and Track Grease, or higher durability LongLife Grease, which adds a bit of drag but stays in when riding through messy conditions.Compatible with:Frame: OSBB Inner diameter: 46mmWidth: 62mm