These flip racks have non-warping metal trays with patented, non-locking rubber feet. The racks are supported by a reinforced steel framework, and move easily on ball-bearing casters. The trays rest flat when down, spaced 1-1/8″ apart. They nest together when up, to permit a wider opening, and won’t tangle. These racks feature adjustable steel springs that permit tension setting as desired. The springs hold the trays in the up position for loading or unloading. The racks are easy to load from bottom to top. Sheets can overhang if retained 6″ from the back. The racks are strong enough to hold glass, lightweight metal, or plastic sheeting. They ship unassembled by truck. Instructions are included.