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Casper

Casper Sleep Box Spring Foundation for California King Mattress

  • Based on 1,050 reviews
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Availability: Only 8 left in stock, order soon!
Fulfilled by Amazon
Arrives Thursday, May 22
Order within 4 hours and 55 minutes
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Size: California King


Style: Foundation


Pattern Name: Box Spring


Features

  • Foundation dimensions 71.5" W x 83" L x 7.5" H | Metal Bed Frame 72.2" W x 76.7" L x 7.3" H | Weight 88.8 lbs. | Hold weight 750 lbs. | Slats distance from each other 4
  • Ships in a compact box and can be easily assembled in minutes - without any tools | Designed and assembled in the USA; Non-Woven Interior and Slat Upholstery
  • 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
  • Engineered with solid wood and rigorously tested for durability and proven to stand up to years of sleep. Slats are positioned a perfect four inches apart for optimal support
  • 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

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


Compatible With Mattress Size: ‎California King


Brand: ‎Casper


Assembly Required: ‎Yes


Ground To Item Distance: ‎7.5 Inches


Manufacturer: ‎Casper Sleep


UPC: ‎192472004812


Global Trade Identification Number: ‎12


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: Thursday, May 22

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

    • 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
    • Well Designed, Sturdy, Easy to Assemble
Size: Full Style: Foundation Pattern Name: Box Spring
I've ordered 3 of these for different locations over the past 3 years. They are very study and easy to put together. Very clever design. Attractive fabric wrap.
Reviewed in the United States on August 18, 2024 by Dawn O then A
    • Great purchase
Size: Queen Style: Foundation Pattern Name: Box Spring
I don't often write reviews but this product is worth it! It is perfect. I purchased a headboard/footboard with side rails from an up scale consignment store. Then purchased a memory foam mattress (Amerisleep, made in USA, excellent!). But the bed was not designed for the weight of a memory foam mattress. I added slats with legs but it didn't raise the mattress up enough. Did my research and found standard box springs can't be used with memory foam. And then I found the Casper box spring specifically designed to solve my problem All the reviews were positive, so I ordered it. It was the easiest thing ever to put together (I'm 68 and didn't need any help!) and it fits perfectly. My new mattress feels even better too! This is very good quality and I highly recommend it if you have an older model bed and want to buy a memory foam mattress! ... show more
Reviewed in the United States on June 9, 2021 by lpa
    • 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)
    • Solid and Quiiiet
Size: Queen Style: Foundation Pattern Name: Box Spring
This is a solid box spring foundation and has a classy look almost a gray tweed type material, ive matched mine with quiet balance frame and a dream cloud 14in mattress all compliment each other perfectly i also added a headboard and it's all perfection but back to the box spring very sturdy and the assembly was so easy it shipped quickly and the sale price was an instant draw . It's quality , it's a good use of your money you won't feel taken. I'd highly recommend this one. ... show more
Reviewed in the United States on August 27, 2022 by Elizabeth L.
    • 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
    • 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
    • Boy! That was easy!
Size: Queen Style: Foundation Pattern Name: Box Spring
A couple of years back, I purchased a twin Zinus "Smart Box Spring" which was basically a grown up lego set and took me at least 1 hour to assemble and then get into the cover. So when I purchased this set, I had prepared myself for the same ordeal. This couldn't have been easier to assemble. There were 2 short pieces that were held together by 2 "pegs" and 2 long pieces held together in the same way. All pieces were clearly marked "Up!" so you could easily figure out how to get the pieces to line up and insert said pegs. It was together in less than 10 minutes! The slats sit on top and hopefully will hold -- I haven't had a chance to try them out yet. W My only "ding" was when we were unboxing the Casper Mattress, we had to be careful to keep the slats from "bunching up" underneath... but that wasn't a huge issue. While Zinus was much cheaper, I was extremely relieved to have this be such an easy assembly and wanted a foundation that I figured was engineered specifically for my mattress. [LCVR] ... show more
Reviewed in the United States on July 4, 2020 by Leopoldo Kaneeny

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