Shimano made a tool (TL-PD30) to adjust the bearings. The blind outboard axle end allowed greater cornering clearance than a typical pedal. Mechanically, they use a combination of ball and roller bearings. Cosmetically, they are similar to the AX pedal, but that's where the similarity ends. AX was never widely adopted, and the PD-7400 returned to standard mounting to the crank arm.