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King 12 Inch Memory Foam Mattress in a Box, Cooling Knit Fabric Cover, Made in The USA of US Foam and Global Materials, CertiPUR-US Certified, Fiberglass Free Mattress, 76”x80”

  • Based on 698 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Dyonery

Arrives Jul 26 – Jul 31
Order within 4 hours and 22 minutes
Available payment plans shown during checkout

Size: King


Style: 12inch Medium-Cooling


Features

  • Cooling Knit Fabric Cover:Cooling Knit Fabric Cover can create a cooling sensation keeping you comfortable while you sleep.The fabric is smooth and comfortable, absorbent,and allows sweat to evaporate easily, keeping your skin dry.This allows you and your family to enjoy a comfortable.This fabric stays cool-to-the-touch due to its superior breathability and temperature regulating properties that move heat away from the body.
  • 3-layer memory foam mattress:Copper memory foam mattress can help you get a good nights sleep by cradling your body in comfort, reducing tossing and turning,and minimizing common sleep disruptions that can result from uncomfortable pressure points or inadequate support.Whether youre a light sleeper or a restless toss-and-turner, a high-quality three-layer memory foam mattress can help you achieve a more restful and rejuvenating sleep experience.
  • CertiPUR-US & Oeko-Tex Standard 100 Certified: Our mattresses are certified by both CertiPUR-US and Oeko-Tex Standard 100, ensuring that they are free from harmful substances. The memory foam and fabrics have been independently evaluated to comply with all mandatory and voluntary safety standards for mattress products.
  • Easy Setup:Our mattresses are easy to setup. They can fit all types of frames, including box springs, floors, adjustable beds, foundations, slatted platforms, and flat platforms. Simply wait for 12 hours for the mattress to fully expand to its original shape.
  • 10-Year Limited Warranty for Worry-Free Sleep: We are dedicated to providing you with the best night's sleep possible through our superior products. If there are any issues with your mattress, please contact our customer support team and they will assist you in resolving the problem. Please note that our mattresses cannot be returned once opened.

Brand: Dyonery


Size: King


Product Dimensions: 80"L x 76"W x 12"Th


Top Style: Tight Top


Cover Material: Most likely a high-quality synthetic material like Polyester or Nylon, or possibly Cotton, but the exact material is not explicitly stated in the provided information. See more


Number of Layers: 3


Fill Material: Copper Memory Foam


Special Feature: Copper infused


Color: Black


Model Name: DYO-MCG120K0002T


Product Dimensions: 80 x 76 x 12 inches


Item Weight: 84 pounds


Manufacturer: Dyonery


Item model number: DYO-MCG120K0002T


Date First Available: November 22, 2023


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Jul 26 – Jul 31

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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Learn more about financing & leasing here.

Top Amazon Reviews


  • Well Worth The Price
Size: Queen Style: 14inch Medium
My husband absolutely loves this mattress. He said it's very comfortable. I've purchased multiple. A little bit of dome damage + physical exertion = cognitively bankrupt! The seller's customer service is awesome! They were and are still so patient and kind. I'm still working with them to get some things sorted re one of the multi purchases but they have provided the best service from the very onset. I messed up and bought not only a Queen size for my King bed but also the copper infused when I have an MCAS & Autonomic Neuropathy caused metal allergy which makes copper the worst reaction because it's such a high energy conductor. It literally spikes my pulse up toward 300 bpm. Neurologist stuttering...you've got a serious problem when they caught it on monitor in hospital. Erm, ya think! Now that I'm on daily steroids it has toned down so I was able to lie on it very briefly to feel why he liked it so much. I have to admit that I did not sleep on it. I wanted to return bit it was opened. The box clearly stated 14" copper mattress. So people, read the boxes before you open!! Screw up #2 re this purchase. I was not on my game cognitively. If I were, I would have not opened it and just refused the package. This one was eager to expand. I've never had anything vacuum sealed expand so aggressively. It came wrapped in very thick plastic and had 3 strips of tape on it. I cut the tape and it immediately began expanding inside of the plastic while still rolled up. Since the return policy is that it must be boxed the seller gave me a small refund. I'd have to have paid a large freight company more than what I paid for the mattress to wrap and ship it fully expanded. That's not happening. It expanded fully within minutes. Seriously, came out like a Jack in the Box. Hubby slept on it that night. Unlike charcoal, the copper has no odor. With the hubby's utter disappointment, I gave it away. ... show more
Reviewed in the United States on May 17, 2025 by Tcsmith38 Tcsmith38

  • Best sleeping 😴
Size: King Style: 14inch Firm
The most comfortable sleep I have had in years. I didn’t realize how badly I needed a new mattress until I slept on this one! It is firm enough yet soft enough for comfort. I love how the memory foam contours the body and provides the right amount of support. It eases my sciatica pain with the right amount of resistance. There are so many mattresses on the market, it is hard to select the right one. Buying this online without testing it first was daring but I made the right decision. I have gone to stores and tried mattresses and ended up with a bad one because those few test moments in the store isn’t enough to really know how the mattress will hold up. Sleeping on it is the only true test. After sleeping on this mattress, I am pleased with my purchase. The mattress appears durable and the price is amazing for the quality you get. ... show more
Reviewed in the United States on June 27, 2025 by Starlight

  • OMG!!!!
Size: King Style: 12inch Medium-Cooling
Omg, omg, omg. I have been in possession of this mattress since 11am this morning, and it's 7pm now; FedEx delivered. My husband works 12, 16 hour intense nightshift "days", and I'm a mom of 3 kids, 2 who are special needs and have wild sleep patterns. I gave this mattress an hour to inflate and decided to just go for it. I have never written a review so quickly, ever. Between cancer treatment body pain and narrow sleeping windows of time, pressure points, headaches, menopause (I turned 39 this week), you name it, I am one darn damaged individual before we ever talk about my better half. We've dropped $1400 on mattresses, we've had automatic beds, it's been a whirlwind of beating ourselves up over the last 9 years. To the reviewer who said "buy the damn mattress", you are a saint! In four hours of sleeping in the last 24 hours, I am a completely different person. This is the holy grail of mattresses!!! THE mattress! No breathing issues, pressure points, locked up back muscle columns, no cramped neck, headache, I took no allergy meds, my knees aren't throbbing, nobody snored, my shoulders don't feel like I've been hoisting sand bags, same pillow and everything else. I'm in PA, the mattress came from SC in 2 days, and holy cow, I must have been a teenager the last time I felt this good. I know I'm typing a novel, but seriously I'm so cheery, joyful, bouncing around, the kids think I've lost it. I blamed the coffee. The mattress is incredible, beautiful, easy to manage, just perfect. The value, at a quarter of what we've spent previously on other mattresses, just to have me sleeping on the sofa regularly, geez, and tucking support pillows, buying crazy expensive pillows, and toppers, sooo many toppers... I feel like a different person, I'm moving like a different person. All the creams and supplements and OTC pain meds, geez louise it was the mattress! Okay, so I bought the 12 inch king size, medium, cooling mattress, in case there's no header to tell ya. There's support, there's squoosh. We've been using 14 inch height mattresses, so super wild the difference between 12 and 14, I felt like I was stepping into it, lol, but I researched the 2 sizes. We thought that mattered, nope! I feel asleep immediately and had no nightmares. I'm really wondering what the last one was pinching bc it can take me a full half hour to fall asleep and then one slammed car door outside our window an hour later and I'm awake again. The usual tossing and turning and the exhaustion of feeling more tired than when I went to bed, and then my joints are cracking and I'm one cranky mama! Absolutely, 100% buy the mattress!!! I'm going to find out very quickly over the weekend whether I may be able to just empty my medicine cabinet. That pays for the mattress itself! Don't even know what I've spent to fix my raccoon eyes, makeups, serums, strips. All the reviews, the searching, the comparing, being scared, terrified of failure again! I've never, ever "wanted" to go to bed like this. Been excited to go to bed. This is really something. I know you all probably are thinking I need decalf and an antipsychotic, but seriously. You found it; Waldo, the needle in a haystack, this is the ONE! You're awesome, you work your butt off, you need a place to turn off and turn on again. This is it, your hard reset and comfort; the keystone. Go you! You earned it! Life does and will get better! ... show more
Reviewed in the United States on January 19, 2025 by Margaux V.

  • Firm but comfortable
Size: King Style: 14inch Firm
It’s been a month since I started sleeping on my mattress and at first I wasn’t sure I was going to like how firm it is. I know I ordered firm but it’s definitely more firm than any mattress I have ever slept on. That being said I love it my back really appreciates it I didn’t realize I needed a bed of this firm. It’s definitely not like sleeping on a cloud so if you’re wanting soft and squishy, this is not it if you’re wanting nice and firm with just enough give and support perfect! ... show more
Reviewed in the United States on July 15, 2025 by Brittany

  • Give it time
Size: King Style: 14inch Firm
We only had the mattress for about 2 weeks now , we love it. But you can’t really know until maybe 6 months yo see if it is going to hold up. For the money so far you can’t beat this bed !!!
Reviewed in the United States on June 26, 2025 by Timothy Grant

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