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Zinus 7 Inch King Metal Smart Box Spring with Quick Assembly, Mattress Foundation, Strong Metal Frame, Easy Assembly

  • Based on 18,666 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon

Arrives Sunday, Feb 8
Order within 23 hours and 6 minutes
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Size: King


Style: 7 inch


Pattern Name: New Quick Assembly


Features

  • STRONG, DEPENDABLE, AND READY IN NO TIME - As if its ultra-durable steel structure and convenient packaging werent impressive enough, our original Smart BoxSpring has been given a quick-assembly upgrade
  • DURABLY ENGINEERED - Durable steel is used to construct the inside framework of this foundation; twin/twin xl sizes support a maximum weight capacity of 350 lbs, while all other sizes can support up to 700 lbs
  • EASIER THAN EVER ASSEMBLY - With fewer bolts and tool-free locking brackets for intuitive setup, assembly takes only minutes to complete
  • THOUGHTFULLY PACKAGED - All parts and instructions are packed into one compact box that ships straight to your door
  • 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

Description

As the backbone for solid mattress support, a box spring that falls short can make or break your night’s sleep. We developed the Smart BoxSpring® with unbeatable durability and rock-solid stability to keep your mattress in shape for years to come. And our latest quick assembly version gives you total confidence when it comes to setup, requiring fewer bolts and ingeniously designed with easy to use, tool-free brackets. With our simple, step-by-step instructions on hand, you’ll have this foundation built and ready to use within minutes. Built with a strong and durable steel frame and a versatile poly jacquard cover that slips right on, the Smart BoxSpring® is the picture of dependability for any mattress. All packed in a compact shipping box with everything included, even our 5-year worry free warranty! Now that’s peace of mind you can sleep on.

Size: King


Material: Alloy Steel, Fabric


Product Dimensions: 78.7"L x 75.5"W x 7"H


Style: 7 inch


Special Feature: Durable


Size: ‎King


Product Dimensions: ‎78.7"L x 75.5"W x 7"H


Special Feature: ‎Durable


Color: ‎Grey


Finish Type: ‎Steel


Included Components: ‎Steel Frame, Cover


Compatible With Mattress Size: ‎King


Brand: ‎Zinus


Furniture Finish: ‎Alloy Steel


Product Care Instructions: ‎Wipe with Dry Cloth


Assembly Required: ‎Yes


Ground To Item Distance: ‎7 Inches


Manufacturer: ‎Zinus


UPC: ‎841550325362


Form Factor: ‎7 inch box spring


Global Trade Identification Number: ‎62


Assembly Instructions Description: ‎1. Unpack the box and lay out all parts. 2. Attach the tool-free locking brackets to the frame. 3. Connect the parts as per the step-by-step instructions. 4. Ensure all connections are secure. 5. Your box spring is now ready for use.


Headboard Material: ‎Fabric


Item Weight: ‎44.1 pounds


Item model number: ‎ZU-ABS-7KS


Date First Available: April 11, 2022


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Feb 8

Yes, absolutely! You may return this product for a full refund within 90 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Very sturdy and surprisingly quiet
Size: King Style: 9 inch Pattern Name: New Quick Assembly
I’m honestly impressed with this foundation. I bought the king size and was expecting it to be heavy and complicated, but it was actually very easy to put together. The frame feels solid once it’s assembled, and it doesn’t wobble or shift when you get in and out of bed. What I like the most is that it makes absolutely no noise. No squeaks, no movement sounds at all. The support is firm in a good way, and the surface feels steady under the mattress. It also doesn’t weigh as much as I expected, so moving it around wasn’t a problem. Overall, it looks clean, feels durable, and holds the mattress perfectly without sliding. The height is perfect to match the regular bed headboard. (4 " works )Great buy. ... show more
Reviewed in the United States on November 19, 2025 by Amaris23

  • Strong and yet affordable
Size: Queen Style: 7 inch Pattern Name: Original
Had never heard of a box spring that is not made from wood. At first, I was skeptical to order a box spring from steel. My skepticism then got slightly worse when I read some negative reviews about "OHM, it takes too long to assemble!" Being an engineer and an optimist upon reading majority of great reviews, I went ahead and placed an order for queen box spring. Not only it arrived in time but it was also well-packed. It is heavy and you will need 2 people to carry the box from outside to your bedroom. Once I unopened the box, I was surprised to find the individual pieces tied up in groups based where they all go. Every single piece is numbered and lettered. A piece numbered "1" connects to another piece numbered "1", numbered "2" connects with another numbered "2". Very simple and easy. The kit also comes with tools. The part breakdown is as per below: A (inner long rail) = 2 B (inner short rail) = 1 C (outer short rail) = 2 D (outer long rail-1) = 2 E (outer long rail-2) = 2 F (Slats) = 10 S (shortest screws) = 8 M (mid-length screws) = 4 L (long screws) = 2 H (nuts) = 10 The best advice is that open the box, remove the cable ties, lay out all parts on floor as per the intended connection and get an idea of who connects to who (without actually assembling). It is otherwise called a "raw" or a "draft" assembly". Once it is done, it takes 30 minutes MAX to connect all components. I then put the cover on it and zipped it up. Voila, it was now ready to be placed on the bed. The moment of truth was moments away. My daughter and I lifted it up and placed it on her queen bed. It fit perfectly. We then put the mattress and lied down on it. It is very sturdy and does not squeak upon rolling. Overall, it is very strong and affordable. Here is the best part. It can be unassembled and moved to another place much easily (than the traditional wood box spring). I highly recommend it. Buy it with full confidence! ... show more
Reviewed in the United States on February 24, 2020 by Vijay

  • Effortless Assembly and Rock-Solid Support – A Huge Improvement Over Older Models
Size: California King Style: 7 inch Pattern Name: New Quick Assembly
I’m really impressed with how far assemble-at-home box springs have come. I bought this California King size box spring and couldn’t be happier with the experience. Setup was incredibly easy—everything fit together perfectly, and I had it fully assembled in under 30 minutes without any frustration. It feels solid and well-built, offering great support for the mattress. The last time I assembled a box spring at home was back in 2018, and that one was a struggle from start to finish. This one was the complete opposite—quick, intuitive, and sturdy. Highly recommend if you're looking for a hassle-free option that doesn't compromise on quality. ... show more
Reviewed in the United States on July 20, 2025 by Michael Accardi

  • Reliable and Sturdy: a Great Foundation!
Size: Queen Style: 7 inch Pattern Name: New Quick Assembly
I recently purchased the Zinus 7 Inch Metal Smart Box Spring for my queen size bed and I must say, I am quite impressed with this product. The assembly was quick and easy - I was able to set it up in just a matter of minutes, without any tools. The metal frame is sturdy and strong, and it provides excellent support for my mattress. I also appreciate the fact that this box spring is only 7 inches high, which makes it the perfect height for my bed. It's not too high, nor too low - just the right height for comfortable sleeping. The design of this box spring is quite smart, too. The metal frame is well-crafted and the corners are reinforced to prevent any wobbling or shaking. The overall build quality of this product is top-notch and I am confident that it will last me for many years to come. The only reason I am not giving this product a perfect 5-star rating is that it does make a slight creaking sound when I move around in bed. However, this is not a major issue and it does not affect the overall performance of the box spring. Overall, I would highly recommend the Zinus 7 Inch Metal Smart Box Spring to anyone who is looking for a reliable and easy-to-assemble mattress foundation. It's a great value for the price, and it has exceeded my expectations in terms of quality and durability. ... show more
Reviewed in the United States on April 27, 2023 by The Feedback Fiend

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