Would have purchased several if we had had any idea of how effective these were, Had had? What an amazing contribution to a night's sleep! At one point, rolled it to store, (fit in a thirty gallon bag with no effort); and, it emerged like new! Hint: the Polysilk cover is a must because any particle [of debris] will adhere to the foam. Have already tossed it on the floor for an [instant] extra bed! If you haven't "sprung" for the Simmons (Plush Pillow Top) Beautyrest mattress, then this upgrade will be the difference between a night's rest and your first great sleep!