Instruction: Generate an answer to the question by utilizing the information contained in the document.

Input:
Question: Does a mattres AND boxspring fit under this headboard or is it matress only?
Document: This headboard is the perfect fit for our small master bedroom and we still have plenty of room to walk around it. It is exactly as pictured and is well made. Very happy with this item.
It was a good solid headboard. I would have preferred a stronger base as it sat a little crooked because of the baseboard trim. I ended up selling it because my new place did not have a long enough flat wall. If your room has windows, measure before buying to make sure it will fit well.
I have the black queen-size version of this headboard, with the black platform bed that matches it. It is an okay headboard on its own but it does not fit correctly next to the bed no matter how you position it, so that they bang against each other somewhat whenever you move. Also, it has a problem with collecting what looks like dust but isn't (just age/wear?)
Fairly easy to put together and fit into king size headboard brackets perfectly. I appreciated that the pieces directly behind your head dont go all the way to the floor (a couple of inches shy) so that you can put cords under there for the alarm clark or what have you. Very important since there are no holes in the back of the unit to fish a cord through.
This is basically an Ikea quality headboard, and you can probably find something similar to it at Ikea for less money. To be honest, I picked up this headboard because I have an Amazon Prime membership and I get free 2-day shipping. Also, I didn't think I could haul something like this in my Honda Fit from Ikea.
This headboard looks really good. It worked great for me as I have a lot of books (was able to fit about 40 of them in the spaces provided). Assembling it was fairly straight forward and took roughly an hour. The only suggestion I'd make is to have the instructions in color. I got one piece backwards (the bottom shelf) and I was at the point of no return. I fixed it by just buying a small can of black paint and painting the exposed wooden side.
Prepac BSH-6643 Sonoma Double / Queen Headboard BlackI bought this headboard, the platform for the bed, and a dresser from "prepac" for my 17 year old son. It is typical assemble at home furniture, but it is attractive AND it was shipped within two days.
I purchased the whole set (platform storage bed and nightstands) and i really liked this headboard. honestly, this would have been the one thing i would purchase again -- not due to the others being good but because i love this headboard. i was nervous because my bed is under a window, but the top of this comes right to the sill on the window. the only complaint i would have is that with the boxspring on the storage platform the bed comes up EXACTLY to the cubbies.
I do not know if it will fit another king bed, but I wouldn't risk it seeing as it doesn't fit its own counterpart.
Fit our king size bed perfectly. Only downside is that there are no screw/bolts holes to attach the meatl frame we have so right now it it being kept in place by the bed.
Answer: I have a box spring and about a 12 inch mattress. These end about 4 inches below the first shelf.  My only suggestion is to take a black marker after assembly to the back 1/8 inch edges so it blends in.  Overall, I love this headboard for the storage   No end tables needed!