These are mattresses made of viscoelastic foam and the first Tempurpedic mattress was introduced by a Swedish tech foam company. Since that time the mattress has become widespread on the International mattress market. Beware though if you go on Amazon you will find that their Tempurpedic mattresses are a lot more expensive than regular mattresses. The reason for this could be because of the viscoelastic foam. Some more history on viscoelastic foam it was first developed by NASA to be put into space shuttle seats. The material has been around for 40 years and it has come a long way since then. It is found in many kinds of products including mattresses. It is a man-made substance that reacts to temperature and heat to mold to the human body. But why these mattresses are so expensive I do not know. The mattresses run in the thousands of dollars on Amazon from $1000 to $4000 dollars. They better be an extremely high-quality mattress to be sold at those prices. They better last a long time as well. The companies that make these mattresses should offer very generous warranties on these expensive mattresses. Let us check out some of these mattresses.