Middle Atlantic U317 3-Space Vented Rackmount Shelf - 17" Depth17 3 4" deep by 5 1 4" high, our vented rackshelf has a 60 lb. weight capacity and a rear flange slotted for horizontal cable management. Made from 16 gauge steel, finished in a black powder coat. Middle Atlantic Products manufactures engineered mounting solutions for all low voltage applications. The company's customer first philosophy places special emphasis on quality, service, and meeting the everyday working needs of end users.