PressFit 30 features an integrated seal, pre-assembled into the cups, to further prolong bearing life. The key difference with PressFit 30 is how the bearings are fitted into the frame. Bearings are housed in nylon cups which are pressed into the frames bottom bracket shell. This bottom bracket is designed for 30mm spindle cranksets. Frames will need a 46mm inner-diameter bottom bracket shell to accommodate this system.