Solid Shelf Add-On Units accept a variety of accessories to adapt to changing needs. Dual layer construction provides maximum rigidity and strength. Open styling allows shelves to be reached from all sides for space efficiency. Fast, easy assembly, no tools required. Shelves with plastic shelf clips easily lock into place on posts and are adjustable on 1" increments. Leveling feet compensate for uneven floor surfaces. Consists of 4 shelves, 2 posts, and 8 joining clamps. Finished in attractive, temperature and moisture resistant Galvanized Steel. Up to a 600 Lbs. capacity per shelf.