Conductive support columns ground wire shelving, preventing accumulation of electrostatic charges. Shelving units measure 64, 72, or 84 in. high; 36, 48, 60, or 72 in. wide; and 18 or 24 in. deep, and hold max 800 lb. Optional 5 in. conductive casters add mobility without compromising protection. Shelf dividers and 4 in. ledges are available.