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Zinus

Zinus 9 Inch Twin XL Metal Smart Box Spring with Quick Assembly, Mattress Foundation, Strong Metal Frame, Easy Assembly

  • Based on 82,336 reviews
Condition: New
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Availability: In Stock.
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Arrives Sunday, Jun 14
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Size: Twin XL


Style: New/upgraded with quick assembly


Features

  • Steel Interior Frame With Poly Jacquard
  • TWIN XL DIMENSIONS - The dimensions of this XL twin size box spring are 78.7 x 38 x 9 inches. The length is 5 inches longer than our Standard Twin size. Please measure your bed frame to ensure compatibility
  • EASIER THAN EVER ASSEMBLY - As if its ultra-durable steel structure and convenient packaging werent impressive enough, this box spring features tool-free locking brackets for intuitive setup, assembly takes only minutes to complete
  • 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 Full, Queen & King sizes can support up to 700 lbs
  • VERSATILE FIT - Compatible with all Zinus mattresses and bed frames; please confirm dimensions before using with non-Zinus products
  • WARRANTY INCLUDED - Included a 5-year limited warranty for the box spring only; a bed frame 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: Twin XL


Material: Alloy Steel, Fabric


Style: New/upgraded with quick assembly


Color: Grey


Included Components: Steel Frame, Cover


Included Components: Steel Frame, Cover


Brand Name: Zinus


Manufacturer: Zinus


UPC: 841550325393


Global Trade Identification Number: 93


Manufacturer Warranty Description: Worry-free 5 year limited warranty included.


Manufacturer Part Number: ZU-ABS-9XS


Model Number: ZU-ABS-9XS


Set Name: Height/Size


Item Type Name: Box Spring


Required Assembly: Yes


Assembly Instructions Description: Easy to follow, step-by-step instructions included


Style Name: New/upgraded with quick assembly


Color: Grey


Furniture Finish: Gray


Form Factor: Rectangular


Shape: Rectangular


Compatible With Mattress Size: Twin XL


Maximum Weight Recommendation: 350 Pounds


Size: Twin XL


Item Dimensions: 78.7 x 38 x 9 inches


Item Depth: 38 inches


Material Type: Alloy Steel, Fabric


Product Care Instructions: Wipe with Damp Cloth


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Jun 14

Yes, absolutely! You may return this product for a full refund within 30 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

    • Good height and easy assembly
Size: Twin Style: Box Spring (Original)
Review Image by Glutenfreesista Glutenfreesista
Review Image by Glutenfreesista Glutenfreesista
The instructions for assembly and the assembly itself is similar to IKEA products. This box spring (original) arrived last evening and I've put it together this morning. Putting all of it together on your own until you have it set up for use takes a little over an hour. It would have been good if the box spring's cloth cover covered the under side as well, so you didn't have to clear up dust more often. I needed this box spring to add some height to my whole bed setup to get in and out of bed easily. It works! ... show more
Reviewed in the United States on May 6, 2025 by Glutenfreesista Glutenfreesista
    • Excellent Purchase
Size: Twin Style: Box Spring (Original)
My husband said it was super easy to put together…in fact he said it was probably the most easily assembled thing we’ve bought in years, and the tools that came with it were “perfect”. Seems extremely well constructed.
Reviewed in the United States on May 30, 2025 by LoLo
    • Excellent lightweight Box Spring!
Size: King Style: Box Spring (New Easy Assembly)
Yes, the directions are basic, but honestly it was super easy to follow and put together. I read other reviews that speak to squeaks, and because of that I used the included wrench to REALLY tighten down every screw. I jumped around my bed afterward and NO SQUEAKS! I love this concept of a king box spring that is light, easy to maneuver and it fit great in my frame. ... show more
Reviewed in the United States on May 10, 2025 by Justina Petrovic
    • Pleasantly surprised....so far...Update ....30 JAN 2021...
Size: Full Style: Box Spring (Original)
First of all, I was pleasantly surprised with the quality of this box spring. Only one night sleeping on it but no squeaks so far. I should add that I will update this review if any problem occurs. Before I ordered this, I read through all of the questions and answers which took a couple of hours. So glad that I did as several customers mentioned the cover and problems putting it on. It is a very tight fit but if I can do it at my age, anyone can do it. A suggestion to the manufacturer would be to add perhaps 1/4 to 1/2 inch more fabric and it would not be so difficult to place over the box spring. I also watched the video twice before I ordered this and that was easy to follow. Four of the pieces were labeled with a yellow sticky that said 'up' which was most useful. My other suggestion would be to label all of the pieces with 'A, B, C, D etc. which would have decreased my assembly time by at least one hour. I did go back and watch the video again while I was assembling. Total time for me to get the pieces in the right order, double-check the placement, tightening of the hardware, etc, was 4 hours. After I got the box spring assembled, I went around each piece and put pressure on each one, to make sure things were as tight as I could get them. I am visually impaired so perhaps that contributed to the amount of time it took me to assemble it. At my age, I am thinking that perhaps I should have had someone make sure I had everything tightened well. If anything loosens up over time, will have someone help tighten it for me. All in all, so far and so good. The mattress I have on top is really heavy and as I stated previously, the box spring has no squeaks and appears to be most durable. In other words, no movement of the box spring. Update to follow if anything should occur. Edit on 26 MAR 2019... Have been using this for 17 months now... No squeaks, absolutely zero problems! Still as satisfied as the day i first reviewed this in October of 2017. And, my recommendation is still that I highly recommend this box spring. Update on 10 OCT 2019.... The 2 year anniversary of this box spring and once again there are no squeaks and zero problems. Still highly recommend this box spring~ Update as of 30 JAN 2021...Absolutely still in perfect condition. Was going to increase the star rating to 5 but don't dare to change it. Truly outstanding and most highly recommend this item for everyone that wants a sturdy and long-lasting box spring. Could not be any more pleased with a product... Most highly recommend... ... show more
Reviewed in the United States on October 14, 2017 by Serenity...
    • Highly recommend
Size: California King Style: Box Spring (New Easy Assembly)
Bed is as advertised and I was able to put it together single handedly in about 45-60mins. The only issue was that I ordered the wrong size but was able to quickly return and get the correct one. Highly recommend!!
Reviewed in the United States on May 20, 2025 by Rob F.
    • ⭐️⭐️⭐️⭐️⭐️
Size: King Style: Box Spring (New Easy Assembly)
Easy assembly! I needed a (9) inch king box spring and this is perfect. It arrived with next day delivery, the price is great for the quality. The base has a washable cover. Would recommend ⭐️⭐️⭐️⭐️⭐️
Reviewed in the United States on May 22, 2025 by JB
    • Good support for boxspring and mattress
Size: Queen Style: Bed Frame
Very easy to put together and feels very sturdy. My mattress actually feels like it’s gained back some firmness. I credit the middle bar in the frame. My old one ran top to bottom but this one goes across.
Reviewed in the United States on May 10, 2025 by Kathleen H.
    • Best Box Spring Ever!
Size: Queen Style: Box Spring (Original)
This product is great, I am 100% satisfied with this purchase. I am using this box spring with a Nature Sleep memory foam mattress. If you have an innerspring mattress your mileage may vary. My review as follows will cover several different aspects of this product and why they are great. Portability: Who knew you could assemble a box spring instead of lugging around a 50+ pound bulky wooden frame? Once assembled, the frame is lightweight and much easier to move around than a traditional box spring. The next time I move I am just going to take it apart instead of it taking up space in the moving truck, very economical in that sense. Assembly: Assembly was very easy, no mechanical inclinations required from the assembler. The set comes with an allen wrench/hex key and you use that to hold bolts in place while you tighten wingnuts with your fingers. Please ignore any reviewer of this product who said it was too difficult to assemble, took too long, or had confusing instructions, they are either lazy or completely incompetent. It took me about an hour to assemble by myself, and it would have taken even less time if I hadn't been half watching TV and drinking a beer while I was putting it together. The instructions aren't written words, but pictures showing which pieces to assemble with which bolts, but if you ever built a Lego set when you were a kid you should be able to handle this. It is easy to tell which pieces should be facing up during assembly, because most have a 'this side up' sticker. The pieces that don't, it either doesn't matter which side is up or you can tell which side should be up because of the notches the slats will fit into at the end. The Cover/ Looks: The zip cover looks nice and the white sides are a soft plush. Make sure you sweep your floor before zipping the cover on though or you might get dirt all over the nice white part. Some people said that the cover ripped when they were zipping it up, that was not the case for me. The cover is a very tight and perfect fit, but the white sides stretch. So when you zip it on, don't just yank on the zipper as hard as you can, pull up on the white parts that stretch and it will make the zipper easier to close. Durability: It seems sturdy enough to me. I have had for two weeks, no complaints. I have unzipped and re-examined the frame and it has not bent or buckled under the weight of two people or any vigorous activity. Could you bend the metal of the frame after you put it together? I guess you could if you tried to, but why would you do that deliberately? Putting a mattress on top of it and using as intended should leave you with no issues. I hope this review provided all the information needed to help in your purchase decision, and I am sure you will be satisfied with this box spring. ... show more
Reviewed in the United States on April 29, 2015 by Brad

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