Warning to those considering this: Most mattress warranties will be voided if you use this frame without an additional bunkie-board or boxspring. The spacing between slats is around 5.5" whereas most mattress warranties are strict about having at most 3-4" between the slats. It has been a real pain to try to find an additional product to put on top of this frame to satisfy our mattress warranty. As a heads-up, these bunkie boards / additional supports can cost almost as much as the this frame does if not more. Very frustrating..