This bottom bracket features a shallower insert compared to our regular PF30-DUB, which makes it perfect for metal frames with internal wires or carbon frames with a reduced contact area in the bottom bracket shell. It will fit Sram DUB crank spindles on a PF30 frame. It moves the bearings out of the frame in order to make a wider and stiffer set up. Bearing wear is greatly reduced with this wider set up compared to a standard PF30 setup with spacers. Choose road bearings for road bikes, cross bearings for mountain bikes and cyclocross.