The mattress is great, but the "box spring" is terrible, and the reason for my two star rating.  The box spring was actually a foundation in that it did not have springs.  It is identified as a foundation in the description, and it really should be advertised as such in the title.  The foundation is made of cheap wood that kept splintering and leaving saw dust everywhere.  We received several slivers putting it together.  Putting it together also took HOURS because there were no instructions for assembly provided, only a checklist of what was included in the package.  It also looked like perhaps it had been returned from another customer because the hardware came in a zip lock bag.  When we placed the foundation on our existing, well-made bed frame, it did not lay flat and wobbled.  Luckily, the weight of the mattress keeps it from moving.  Really disappointing.