Wheels Manufacturing BB30 Bottom Bracket Adaptor for GXP Cranks adapts 22/24mm Spindle Cranks (SRAM/TruVativ) to work on BB30 frames. Simply tap the adapters into the 6806 bearing in the BB shell, then install the spindle and cranks. Use Wheels Mfg Crank Spindle Spacers to adjust your chainline, or take up any side-to-side movement in your cranks. These spacers are machined from engineering-grade Delrin.