I bought a 1.5” mattress. I wanted to try this Gel memory foam topper first. I was skeptical but its a perfect solution, soft but firm enough for back sleepers too. I you likes sleeping on a rock-hard mattress and you dont, try it!! Or buy a smaller width and put it on your side of the bed -- might look funny but well worth getting rid of the hip and shoulder aches side-sleepers can experience on a hard mattress.