This Edsal UR1848P-BLK storage rack has a frame made of steel for strength with a smooth black powder coat finish for resistance to corrosion, 5 adjustable particle board shelves and a 4,000 lb. capacity when the weight is evenly distributed across all shelves. It is suitable for organizing and storing items. The shelves are supported by double-riveted beams and braces for strength and adjust in 1-1/2 in. increments to accommodate items of varying heights. The posts on this shelving unit have a 2-piece design so it can be assembled vertically to create one 72 in. H x 48 in. W x 18 in. D unit or assembled horizontally to create one 36 in. x 48 in. x 18 in. (H x W x D) unit with 2 shelves and one 36 in. x 48 in. x 18 in. (H x W x D) unit with 3 shelves. (H is height, the vertical distance from lowest to highest point; W is width, the horizontal distance from left to right; D is depth, the horizontal distance from front to back). This shelving unit's rivet lock design requires no nuts or bolts for assembly. Assembly instructions are included; tools for assembly are not included.