Hallowell's DuraTech Pass-Thru Shelving features a strong, durable frame that requires no cross braces, so you can access it from all sides. Each unit has four 14-gauge steel posts, allowing them to be individually located, bolted side-by-side or bolted back-to-back. Includes heavy-gauge, cold-rolled steel shelves. Top and bottom shelves are fixed, while the middle shelves are adjustable. Bottom shelf is designed to prevent debris from collecting underneath.