An all new concept in bed rail technology. When not in use, the rail stores away between the mattress and box spring, completely out of sight. No more hassles making the bed or changing the sheets. Easy to assemble, no tools required. The patented "Gap Guard" feature eliminates gaps between the mattress and bed rail side wall by locking the bed rail securely to the mattress. A 20 inch high side wall will accommodate an extra thick pillow top mattress. Requires a box spring. 43 inches L. Weighs 9.5 lbs. Ages 2 to 5 years. 20 in H x 1.5 W x 43 L.