We ordered two twin xl. They are for our king bed. We have one in our spare room and I slept on it and loved it, so we purchased two more for our bed. It is a little too firm f6my husband, so I just purchased a foam gel topper. Works great. Followed all the directions mattress expanded well. Fits the king bed perfectly. You can't beat the price. I got them when they were on sale. Not too hot to sleep on, and we notice no smell. I will definitely buy these again.