We didn’t expect to assemble this boxspring, but found it perfectly ok because we could see how well is boxspring was constructed! This is so worth the 30 minutes it took to put together.  The framed periphery fit perfectly inside our platform bed and provided just a bit more height for us now that our cats are gone.  It fit directly onto our platform slats, and we now can return to a normal elastic sheet vs tucking a larger one into  platform. The slats are an ergonomic 3 inches apart which provide excellent support.  We received delivery within one week and it was delivered right to my door!  I highly recommend this 4 inch boxspring!