Designed for heavy-duty use. The boltless design allows for quick & easy assembly. The powder-coated finish is rust resistant & durable. The shelving unit can be assembled either horizontally or vertically, depending on your storage needs. Each unit includes rugged particle-board shelves. Assemble with a rubber mallet in less than 30 minutes. Series Name: Alera 3800 Series Shelving; Number of Shelves: 4; Shelf Depth: 16"; Shelf Capacity (Weight): 640 lbs.