The mattress arrived all rolled up. At first I was nervous every with the size. The instructions said to wait a full 48 hours for the full size of the mattress to be correct. My mattress took a full 72 hours to get to about 78 inches in length. It is only made a foam, not much to it. The bunkbed we bought states no more than a 6" inch mattress for the top. I am am definitely going to try to find an egg crate for the top of this mattress. I did purchase on sale and had a coupon code so overall, if it lasts a couple of years I will replace and feel I got my money's worth.