Mattress Saver | Extend The Life Of Your Mattress | Curve Medium-Soft Mattress Mattresses wear out over time, often resulting in a sag from repeated sleep in the same place. Sags are like craters that are deepest at the center, not block-shaped, so square foam is not the best solution to support a mattress sag. That is why Curve is designed with a gradual arch to fill the sag inversely from the bottom up. Curve is made from high quality mattress foam that provides support with flexible comfort. One Curve is recommended under each sagging area for best results, so most queen or king mattresses used by two people will require two Curves ? one under each sleeper, placed independently for individualized comfort. Curve is typically placed under the mattress with the curved side UP to fill sags inversely from underneath, but for heavier or thicker mattresses, it can be placed on TOP of the mattress with the Curve side DOWN to fill the sag from the top and still provide a level lying surface. Curve is MADE IN THE USA in clean U.S. facilities from materials that are certified by CertiPUR-US to be clean and toxin free. IT WORKS! Curve MEDIUM-SOFT is designed for mattress sags up to 1" deep. Curve boosts the sag from under the mattress. QUALITY: Made of high quality mattress-grade flexible foam so you won?t feel a hard board beneath you like other sag repair products. Curve may also be inverted and placed on TOP of mattress (over the sag), if desired. SIZE: 1.5?H x 24?W x 60?L PLACEMENT: Use 1 Curve per sagging area (two for most queen or king mattresses). Curve's arch fills sags to renew and rejuvenate worn mattresses with a depression from repeated sleep in the same spot.. 100% MADE IN THE USA from CertiPUR-US certified clean foam. 100% U.S. customer support.