There are numerous advantages to getting wire shelving as opposed to a solid deck shelving system. Wire shelving features ventilated racks that let light in and allow air to flow through. These units are easy to maintain, fully adjustable, and incredibly durable, supporting up to 600 pounds per shelf (evenly distributed). If you wish to expand your wire rack shelving, consider purchasing an 30"d Wire Shelving Add-On Unit or upgrading to the 30"d 5 tier Wire Shelving Unit.