Originally I had a 3" foam mattress topper. It was too thick and made my mattress too high. I also didn't want to deal with the chemical smell. However, my mattress was too hard to not have any topper. I found the extra thick bamboo top and it's perfect. It adds very little height to the mattress but it did add a perfect layer of comfort. It's made in the USA and has no smell. I love it!!