Box Two External Euro Bottom Bracket (24mm)

Box Two™ External bottom brackets feature cold-forged & CNC-machined alloy cups, dual-labyrinth bearing covers & precision sealed bearings. They are the perfect match to Box Three™ & Four cranks, & the ultimate upgrade to the budget BBs sold w/ most cranksets. Box Two™ External Bottom Brackets are designed to fit all 24mm crank spindles & frames w/ 68 or 73 x BC 1.37" bottom bracket shells.