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Casper

Casper Sleep Box Spring Foundation for California King Mattress

    • Based on 1,005 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon
Arrives Sunday, Jun 9
Order within 10 hours and 3 minutes
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Size: California King


Style: Foundation


Pattern Name: Box Spring


Features

  • The Casper foundation is engineered to provide excellent support under your Casper mattress but can be used with other mattresses in place of a traditional box Spring
  • Designed and assembled in the USA
  • Compatibility-works with any mattress; Requires a simple metal bed frame, slatted bed frame, or a platform (if you want extra height); The foundation should not be put directly on the floor
  • Ships in a compact box and can be easily assembled in minutes - without any tools

Description

Our foundation provides excellent support under any Casper mattress and can be assembled in minutes -- no tools required. It can also be quickly disassembled if you are moving or need to maneuver around tight corners. Older box Springs’ slats tend to be too far apart, leaving room for a mattresses. Our foundation’s slats are positioned a perfect four inches apart for optimal support. Engineered with solid wood, it has been rigorously tested for durability and proven to stand up to years of sleep.

Size: California King


Product Dimensions: 83"L x 71.5"W x 7.5"H


Special Feature: Care Instructions Spot clean the fabric with a mild detergent and let air dry before you continue using. See more


Color: Grey


Included Components: 2X - Center Support Beam, 2X - Side Rail, 4X - Corner Pin, 2X - End Rail, 2X - Foundation Support Slats / Box Spring Support Slats See more


Size: ‎California King


Product Dimensions: ‎83"L x 71.5"W x 7.5"H


Special Feature: ‎Care Instructions Spot clean the fabric with a mild detergent and let air dry before you continue using.


Color: ‎Grey


Included Components: ‎2X - Center Support Beam, 2X - Side Rail, 4X - Corner Pin, 2X - End Rail, 2X - Foundation Support Slats / Box Spring Support Slats


Brand: ‎Casper


Assembly Required: ‎Yes


Item Weight: ‎83.8 pounds


Country of Origin: ‎China


Item model number: ‎FN00000065


Date First Available: August 16, 2019


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Jun 9

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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Similar Products

Top Amazon Reviews

    • Designed to work with Casper System
Size: Queen Style: Foundation Pattern Name: Box Spring
Bought Casper system in Queen for my 270 pound football player son. Easy assembly and sturdy. Second Casper Foundation we've bought. This time we're using a Casper mattress. (Master bedroom has a king with conventional matress on Casper foundation.) Bought the Casper bed frame as well. While the frame was more expensive than generics, it was worth it get something STURDY. Center supports add strength. Bed frame a perfect fit with the foundation. Casper mattress purchased separately at COSTCO at better price than Amazon. Delivery was smooth. I was able to assemble by myself. Recommend opening box and bringing parts upstairs one at a time to assemble in the bedroom. ... show more
Reviewed in the United States on September 4, 2023 by CAPT James Kent, USNR (ret)
    • Works Pretty Well
Size: King Style: Foundation Pattern Name: Box Spring
I got a new bed frame that needed a box spring. After evaluating a number of options I gave this a shot. It's pretty easy to assemble and it provides great support for my Costco Casper mattress. The nice thing is that when I eventually move this will be much easier to deal with than a box spring.
Reviewed in the United States on August 21, 2023 by Daniel
    • This is the one to buy!
Size: California King Style: Foundation Pattern Name: Box Spring
If you are looking for a box foundation, this is the one to get! We searched and searched and read tons of reviews on all different types of box springs. After reading so many, we landed on this from Casper. We had purchased a memory foam mattress, and realized it needed just a bit more support than the mattress alone. The biggest difference between this box spring and the others is the material. We had read some reviews about metal box springs, and heard that they eventually would squeak. That is a dealbreaker for us. Casper foundation is made of a sturdy material and comes with the Casper reputation. It was incredibly simple to put together. Just like any square item, you will want to ensure that they are lined up well prior to inserting the pegs. No tools were required. However, we did use a hammer for ease of positioning. It wasn’t necessary though. The difference with this boxspring underneath the mattress is night and day. It was well worth the additional price, and just like purchasing my mattress, the money was well spent. ... show more
Reviewed in the United States on December 29, 2022 by Annie Townsend
    • Perfect solution
Size: California King Style: Foundation Pattern Name: Box Spring
We purchased the Casper hybrid mattress for a new bedroom set, but it was way to low, so we purchased this item to elevate the mattress. It raised it 7” and gave the mattress excellent support. We’re now sleeping 💤 like a dream, a GOOD dream.
Reviewed in the United States on June 24, 2023 by RICHARD N.
    • Horrible customer service
Size: Queen Style: Foundation Pattern Name: Box Spring
The foundation is fine. It’s stable and doesn’t squeak. But the Casper customer service is HORRIBLE! We moved and the movers managed to lose three of the four pegs that hold the foundation together. Although just plastic pegs, they are critical to assure that the foundation stays together. I called Casper customer service. The third person (Liz) told me that she would look into it. About five days later, she told me that since the foundation was out of warranty, she couldn’t help me. I offered to pay for the pegs, but she said that’s impossible for Casper to do. Really? Casper is capable of taking orders and also capable of shipping pegs that are part of warranty claims. They just have no interest in delighting their customers. It’s been a week and Liz is ghosting me after I asked that her supervisor call me. In summary, a decent product, but don’t expect any help from Casper customer service. ... show more
Reviewed in the United States on August 12, 2023 by Marie M
    • A very strong and heavy platform that gives confidence when laying in bed
Size: King Style: Foundation Pattern Name: Box Spring
Review Image by Larry Larry
Review Image by Larry Larry
We like this platform which we have resting on a metal bed frame and it feels solid enough to support our winkbed. I spent a lot of time being sure everything could handle the weight of what it would carry, meaning the bedframe had to be able to support the weight of the platform plus the mattress, and the platform had to be strong enough to carry the weight of the mattress. All those weight limits are in the various item specifications. I hope that helps. P. S. I attached two photos (left and right) not often seen showing how the platform rests on the metal bed frame. You can see the width of the wood and how most of the width is supported by the lip of the frame. ... show more
Reviewed in the United States on September 24, 2022 by Larry Larry
    • I'm still having nightmares about the PEGS
Size: Queen Style: Foundation Pattern Name: Box Spring
Dude, what a total nightmare it was putting this together. There are four big pegs. It says so in the " simple" directions. The trend of providing 4 step directions with minimal explanation needs to end! It works in favor of the company by implying that it's so easy to put it together and if you have any questions and/;or it's not working, then just read the minimal steps again. The pegs don't line up, but when you first fit them in, it seems as if all four will line up, then, when they don't, you think, ok, I just have to pull this one peg out again and all four corners will line up . Right!!! The pegs come out " sometimes " but not " every time" you need to readjust the sides of the frame. The good news here is, that I never finished putting this together perfectly...one of the pegs is inserted only half way, and one of the sides is not aligned and I gave up, thinking the whole thing may have in on me in the middle of the night. That never happened and have been sleeping on it fine for over two months now. It is sturdy as you need it to be. I advise two people get mad at eachother and put this thing together as a team, or spend the extra money to save the hassle and risk of putting it together in a haphazardly fashion. ... show more
Reviewed in the United States on December 26, 2021 by ChrisCross
    • Twin Sized
Size: Twin Style: Foundation Pattern Name: Box Spring
I took a gamble buying this since the Amazon site has the wrong size shown. It lists the size of the Casper Twin foundation as 79" in length. That's the right size for a Twin XL (where it shows the same dimension), but would be too long for a twin bed frame and a twin mattress. Fortunately, the twin XL foundation was out of stock, so I reasoned that it couldn't be the same as a twin (which was in stock). I assembled it in about 10 minutes. Good instructions and very easy to do. And measured it. It's the proper length, which is 74". Makes sense, but worth noting so other folks can order with a bit more certainty. Haven't gotten the bed not the mattress yet, but I'm happy with the purchase. Especially so, since the mattress and the foundation together were about $150 less than the exact same mattress by itself! ... show more
Reviewed in the United States on January 9, 2022 by Roger Ronald

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