Add-A-Shelf® Starter Unit, 4-tier, 36"W x 21"D, (2) wire shelves on top & bottom with patented QuadTruss® design, (2) Add-A-Shelf® intermediate shelves, (4) 74"H Red-i-Pak® posts, includes (4) bags of split sleeves & (2) bags of Add-A-Shelf® collars, chrome finish, NSF