The wishes of cyclists and shop technicians around the world were answered when Chris King introduced the PressFit 24mm Bottom Bracket. Their reputation for turning troublesome components into reliable and easy to tune parts was solidified with this PressFit 24mm Bottom Bracket. First, the bottom bracket holds 24 stainless steel ball bearings in each cartridge. They're not just any ball bearings Chris King manufactures them to a precision that is much higher than industry norms to ensure reliability and long life. The bearings are even easy to service with the Grease Injection Tool sold separately. This lets you easily add fresh grease and purge the old gunk. The Chris King PressFit 24mm Bottom Bracket fits 24mm road cranks and 86. 5mm bottom bracket shells, 24mm mountain cranks, and 89. 5mm or 92mm bottom bracket shells, out of the box. 86. 5mm shells and 2422mm road cranks will require King's Conversion Kit 7, while 2422mm mountain cranks and 89. 5 or 92mm shells will need Conversion Kit 6.