The BB30 bottom bracket allows you to pair 30mm spindle cranks to 42mm inner diameter bottom bracket shells.
Cannondale pioneered this standard along with specially-designed cranks and many have found the benefits to them. Road versions have a 68mm width, MTB has 73mm. These are also the bearings you can use to replace bearings in PF30 cups.
Low drag, long life Standard Bearing, with hardened-steel races and CeramicSpeed’s super round balls.