Cambro Speckled Gray 4 Solid Shelves High Density Mobile Unit, 21 x 36 x 67 inch -- 1 each.Camshelving is the most hygienic high density storage system available. Raised track ensures dirt will not get trapped, and is easy to clean. Aluminum track and stainless steel hardware is non-corrosive. Easy glide floor track simply connects to the bottom of the Stationary Camshelving Unit. No bolts or drilling into the floor is required. Active aisle of 30"-36" provides easy access to all stored product. Raised track provides a smooth and level surface to easily roll mobile units. It ensures dirt will not get trapped, and is easy to clean. Grooved casters roll easily and securely on raised track. Can be used on any surface, including tile and choppy floors.