The open wire construction of the Erecta Shelf minimizes dust accumulation and allows a free circulation of air, greater visibility of stored items, and greater light penetration. Grooves on shelves position and lock shelves to the Erecta Shelf uprights (sold separately). The unit is assembled in minutes. No nuts, bolts, or special tools are required. Shelves can be placed at 5" (127mm) intervals along the uprights. Erecta Shelf Shelving can also be used with Erecta Shelf wall mounts. Durable chrome-plated finish. Important: When ordering by components remember that stability decreases as the ratio of height to width increases. Freestanding Erecta Shelf units should be kept as wide and low as possible. Shelves up to 48" long have a load rating of 800 lbs. equally distributed. 60" long shelves have a load rating of 600 lbs. equally distributed. Assembled unit's maximum load capacity is 2000 lbs. per 4-shelf unit equally distributed.