All welded construction to provide maximum strength and durability. Hi-tensile strength, 1'' Square aluminum alloy tubing. Is used for frame and cross supports. Pan slides constructed of extruded aluminum alloy angle and welded to frame. The bearing surface has raised beads to keep pans from shifting on slides. Four 5'' heavy-duty casters, two with brakes. Open Tray Rack, mobile, holds (18)18'' x 26'' or (36)18'' x 14'' trays, all welded aluminum construction, closed sides, solid bottom, welded slides 2-1/8'' O.C., w/4 5'' casters (2 w/brakes), NSF