Bombproof for Freeride & DH extremes. Features oversized cartridge bearings to produce a super durable external BB system. Purpose-built with CNC machined AL-6061 cups, chromoly spindle, & extreme strength by design. Bearings 2 x sealed oversized cartridge bearings Weight 365 Grams Chainline 51 MTBMaterial Axle Cr Mo H/TAxle Bore Thread M12 Material L&R Cups CNC-Machined Steel, CNC-Machined Alloy BB Shell Wide 68mm Upcharge Alloy Cups 28 NT