Thick MDF boards sit on a metal frame here, giving a flat deck that small screws and washers cannot fall through the way they do on open mesh. Every unit measures 72 inches tall, 36 inches wide and 18 inches deep, holds 440 lbs per tier and 2200 lbs in total, and four of them come in the order. A reinforced rib runs under each board to limit sway, and two anti-toppling devices anchor the frame once it is fully loaded. Rolled edges take the sharpness off the shelf lips, while eight non-slip pads keep the feet from sliding on a sealed floor. Shelf spacing is set by the installer, so the same rack suits paint cans, folded drop cloths or bins of holiday decor in a garage, kitchen or warehouse.