First you must ensure that the bottom bracket bearing size is compatible with your crank’s spindle diameter. If you have eeWings, then any of our 30mm Hellbender Neo or 30mm Hellbender 70 bottom brackets will work with the 30mm spindle of the eeWings cranks, and if you have a DUB crank, then any of our 29mm (DUB) Hellbender 70 Bottom Brackets will work with the 29mm spindle DUB cranks.
Second, you must ensure that you have enough available crank spindle length to pass through the bottom bracket shell and the bottom bracket itself. Our external bottom bracket cups are 11mm wide each (including the seal) and our press-fit 41/92 bottom bracket adds an additional 2mm of width on each side (including the seal). Therefore, you must have at least an additional 22mm of available crank spindle length for our external cup options, and an additional 4mm of spindle length for our press-fit 41/92 option.