Phil Wood 6903 Sealed Cartridge Bearing Go to amazon.com Related posts Check expert advices for 6903 bearing? FeatureBearing I.D.: 17mmBearing Manufacturer Number: 6903Bearing Number: 6903Bearing O.D.: 30mmBearing Thickness: 7mm DescriptionPhil Wood Upgrade sealed cartridge bearing. Features: For upgrading Hollowtech, MegaExo and X-Type Bottom Bracket