ZINUS Quick Lock Metal Smart Box Spring / 9 Inch Mattress Foundation / Strong Metal Structure / Easy Assembly, King

(10 customer reviews)


  • Steel Interior Frame With Steel Slats and a Poly Jacquard Cover
  • HASSLE & HEADACHE FREE – The Quick Lock Metal Smart Box Spring comes together with easy-to-follow instructions, fewer bolts and absolutely no headaches; assembly that’s intuitive and packaging that seems to defy the laws of physics – now that’s what we call a new-age box spring
  • DURABLY ENGINEERED – A durable steel frame is used to construct the interior framework of this foundation; twin size supports a maximum weight capacity of 350 lbs, while all other sizes can support up to 700 lbs
  • HIGH PROFILE DESIGN – A 9 inch height is perfect for shorter mattresses or for those who enjoy their bed higher off the floor
  • THOUGHTFULLY PACKAGED – All parts, tools and instructions are packed into one compact box that ships straight to your door; Quick Snap assembly system makes set-up intuitive and stress-free
  • Worry-free 5 year limited warranty included; box spring only, a bed frame or platform bed is required to support this foundation and is sold separately


We like to think of the Quick Lock Metal Smart Box Spring as the 2.0 version of your traditional mattress foundation. Made sturdier than ever by its substantial steel frame and with its game-changing assembly method, we’ve developed a better way to deliver great sleep to your door. Created with closely spaced slats to accompany your latex, memory foam or spring mattress, this durable box spring comes in three different thicknesses so your bed can be as short or as tall as you like it. The Smart Box Spring features our fool-proof Quick Lock assembly system, meaning you spend less time screwing in bolts, and you get to be pleasantly surprised by how simply and quickly it comes together. You may even pat yourself on the back once you’re done (in fact, we encourage that). We’re so sure of this foundation (along with hundreds of happy customers) that it’s backed by a 5 year worry-free warranty, so you can sleep confidently for years to come.

From the manufacturer

Quick Lock Box Spring

available in 4, 7.5 and 9 inches profiles

Support for Any Mattress

quicklock slats

A New-Age Box Spring

Build It, Stress-Free

Our Quick Snap assembly process is much like it sounds – quick and yes, a snap to set up! Steel slats hold up beautifully to everyday use, and are easily secured to the structure by applying pressure, not screws. And voila! An ultra reliable foundation.

quick assembly icon

Handyman Skills Not Required

Ready in No Time

Simply unbox, assemble the framework and zip on the durable cover for years of unparalleled mattress support. All with just a friend’s help and less than an hour of your time. Now that’s what we call convenience.

Are any tools required to assemble my box spring?

This box spring is shipped with everything you need to assemble it – all parts, tools and instructions can be found efficiently packed in the shipping box.

Does this box spring require a bed frame?

A basic metal bed frame or platform bed is required to support this box spring. Add your mattress, and you’ve got the dynamic trio for rock solid support.

What kind of mattress can this box spring support?

Our box springs are designed to do it all! Rest your memory foam, latex or spring mattress on top for smooth snoozing.

What is the distance between slats?

For Twin and Full sizes, spacing is 3 inches. For Queen and King sizes, spacing is 2.9 inches.

Additional information

Weight 59.9 lbs
Dimensions 79 × 75 × 9 in
Product Dimensions

79 x 75 x 9 inches

Item Weight

59.9 pounds



Country of Origin


Item model number


Fabric Type

Steel Interior Frame With Steel Slats and a Poly Jacquard Cover

Assembly Required


Warranty Description

Worry-free 5 year limited warranty included.

Batteries Required


Included Components

Foundation Steel Slat Cover



10 reviews for ZINUS Quick Lock Metal Smart Box Spring / 9 Inch Mattress Foundation / Strong Metal Structure / Easy Assembly, King

  1. Karin

    PerfectI have a sweetheart of a dog (actually I have three sweethearts) and they like sleeping on my bed. One of these is a small 24 pound dog who is all muscle (not fat), with the shortest legs. Sort of like a white fluffy dachshund…but is a Maltipoo. Since he’s sturdy and not fat, dieting won’t help, but that muscle weighs a lot and even though he’s not big, he’s heavy. I worried about his legs jumping down from the bed. I have a ramp, but he likes to jump. My bed was so high, I really worried. This took my bed down quite a bit, maybe even a few inches shorter than necessary, but my Maltipoo can get down very easily now, almost steps down (his body is long). I know it’s so much easier on his legs. Benefit for me too… My feet don’t dangle when I sit up and getting in and out of the bed is much easier. This is very nice and sturdy and looks well made. I am finding that I can easily move the whole bed with a knee push now and changing the bed is almost a breeze. Before I’d really struggle with my heavy platform and bed, this slides across my floors with easy. I love it. Just be aware that the height is not high. So, if you have an unusually high mattress… you’re good to go.

  2. J. Mack

    Very happy with purchase – Sturdy and VERY easy assemblyI usually only write reviews if I’m VERY happy with something or VERY unhappy. In this case it’s the former. The assembly and instructions were great. Even included a ratchet tool to use instead of the usual Allen wrench, which was really nice. Extra parts included, which I didn’t need, as nothing was missing. All the metal parts fit together perfectly. ZERO frustration. Cover fit on easily and did it myself without help. Fit in bed frame like it was made for it and SO solid. I feel like this thing would last a lifetime. Even if the cover gets worn, I’m sure it would be perfectly useable without the cover. I hope one day in 50+ years as an old woman that I die in my sleep on this thing 😉

  3. GriselBel

    Great design and strong and easy assembly. Two people can manage easily. Highly recommend it.I love that they provide the ratchet tool you need to make screwing the pieces together so easy. The design is sleek and while the metal is fine, it is really strong and together makes the frame heavy. The encasement is well sewn and designed. Once the mattress is on, the bed feels so sturdy and comfortable. We have a sleigh bed and we had simply put our 15 inch serta sealy luxury mattress upon the slats without a box spring because it would make the bed too high for me. After researching for a better option such as having plywood placed on the slats, would not solve the discomfort in the middle caused by the center legs. So now we enjoy a wonderful rest on our bed because of this new box spring.

  4. Ryan M.

    Worth every pennyI don’t usually do reviews, but I wear really impressed with this box spring. My daughter is not gentle and gone through the wooden ones we get. I finally got fed up and looked into metal ones. The reviews were generally favorable for this unit so I took a shot.Worth every penny. It was very easy to set up, feels very sturdy and not overly heavy. The concert was a breeze to put on, instructions were super easy to follow, and I had it all put together in about 10 minutes.

  5. Heather Richardson

    Very sturdyThis is very sturdy and relatively easy to assemble. It takes a bit of time because there’s many pieces but it’s easy to do

  6. IndianaTraveler

    I will never go back to traditional box springs!These are absolutely better than traditional box springs. These arrive in disassembled in a long narrow box so moving it to the room it will be used in is easier than maneuvering a large and clumsy box spring through the house is gone. This unit is extremely easy to assemble and becomes a very strong base for the mattress. I have bought several of them and I use them with foam mattresses and they work great!

  7. sas

    My best purchase so far this year.Completely satisfied with how this item arrived and how easy it was to assemble. Very high quality for the price and exactly what I was looking for. Would definitely purchase again if needed for another room!

  8. Wookie

    Kinda noisy.I bought this for my 14″ mattress. It’s a good height and doesn’t have my mattress hanging too high over my footboard. Unfourtnantly it does kinda of make a few metal clanking around the middle part of the bed but i truly am happy i found it. Besides that i like it

  9. R. Grande

    4″ Height – Perfect Complement for 14″ Hybrid MattressOnce we settled on a 14″ mattress to replace our 30-year old 8″ high Somma 8″ waterbed mattress, we realized that the additional 6 inch height with the old waterbed spit queen foundation would mean our feet wouldn’t touch the floor when sitting on the edge of the bed (we’re 5′ 7″ and 5′ 3″ tall) and the mattress would hide a good part of our existing Queen Anne headboard. If we had to purchase a standard split queen 4″ or 5″ foundation it would have cost $350. This was the most cost-effective solution as we had no problem carrying the box upstairs (other than it was better with 2 people because of the weight) and it was very easy to assemble. I was even able to get the zippered cover on the assembled frame by myself. We wanted to be sure the foundation was solid so that there would be no concerns if we needed to make a mattress warranty claim down the road . The steel slats are solid and tightly spaced (less than the minimum 4″ recommended) so the mattress is well supported with no squeaks. Would buy again in a heartbeat!

  10. Amethyst

    Amazing product for chubby couples (250-450lbs )Was able to set it up all by myself, easy assembly and can hold up my whole family in bed. Including 2 beagles a cat and my son haha

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