I bought the bed for my seasonal trailer in Wells Maine. It is very sturdy and perfect for a cottage style bed. The 12 inch memory foam mattress fits perfectly on the bed. I did not put it on a box spring and do not think one is needed. The bottom of the mattress has a fabric on it that keeps the mattress firm. However, I will periodically check under the bed to make sure the mattress is not sagging in between the metal slats. So far so good.