- Box Two™ External bottom brackets feature cold-forged and CNC-machined alloy cups, dual-labyrinth bearing covers and precision sealed bearings. They are the perfect match to Box Three™ and Four cranks, and the ultimate upgrade to the budget BBs sold with most cranksets. Box Two™ External Bottom Brackets are designed to fit all 24-millimeter crank spindles and frames with 68 or 73 x BC 1.37-inch bottom bracket shells.
Compatibility |
Box Three™, Box Four™, Shimano HollowTech II, RaceFace X-Type |
Material |
6061-T6 Aluminum |
Shell Width |
68/73mm |
Spindle Type |
24mm |
Thread |
1.37 Inch x 24 TPI (English) |
Weight |
105 grams / 3.7 ounces |