DW’s Delta Tri-Bearing System employs ball bearings in three critical areas: the hinge, spring rocker and both sides of the post casting. DW’s patented Delta ball-bearing hinge is a state-of-the-art lightweight aluminum design that incorporates ball bearings at both sides. The adjustable spring rocker and post casting also utilize ball bearings for smoother movement at the hex shaft, completing the TriBearing System.