14 Inch Firm King Size Mattress in a Box, Copper Memory Foam King Mattress with Graphene Cooling Cover, Firm King Size Bed for Back Pain Relief, CertiPUR-US Certified, Foam Made in USA
Condition: New
Buy Now, Pay Later
As low as
/ mo
Learn more
- – Up to 36-month term if approved
- – No impact on credit
- – Instant approval decision
- – Secure and straightforward checkout
Ready to go? Add this product to your cart and select a plan during checkout.
Payment plans are offered through our trusted finance partners Klarna, Affirm, Afterpay, Apple Pay, and PayTomorrow. No-credit-needed leasing options through Acima may also be available at checkout.
Learn more about financing & leasing here.
Selected Option
Free shipping on this product
30-day returns
Learn more
30-day refund/replacement
To qualify for a full refund, items must be returned in their original, unused condition. If an item is returned in a used, damaged, or materially different state, you may be granted a partial refund.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
Availability:
In Stock.
Arrives
Jan 10 – Jan 11
Recently Viewed
Size: King
Style: Firm - Gold
Features
- Cooling Graphene Cover: This mattress features a graphene knit fabric cover that provides a cool and comfortable feel throughout the night. Its breathable, smooth texture efficiently wicks away heat and moisture to maintain an optimal sleep temperature. The hidden zipper design allows for easy removal of the cover without flipping the mattress, simplifying cleaning and maintenance.
- Advanced Memory Foam Layer: The copper-infused Aerofusion memory foam layer contours to your body, offering personalized, pressure-relieving support that adapts to your unique shape and any sleeping position. Meanwhile, the natural properties of copper help eliminate odors, reduce the risk of skin irritation, and promote a cleaner, healthier sleep environment.
- Effortless Setup: Our mattress is compressed, rolled, and packed in a compact box for easy delivery and setup. It is compatible with different types of frames, including box springs, slatted platforms, foundations, flat surfaces, and even floors. Simply unbox the mattress and allow 24 hours for it to fully expand to its original shape.
- CertiPUR-US and Oeko-Tex Standard 100 Certified: Our mattresses are certified by both CertiPUR-US and Oeko-Tex Standard 100. All components, from the premium memory foam to the breathable fabrics, are rigorously tested for harmful chemicals and volatile organic compounds, delivering a safe sleep environment you can trust.
- 10-Year Limited Warranty for Worry-Free Sleep: Built with high-quality materials, our mattress is designed for lasting comfort and durability. We stand behind our product with a 10-year limited warranty, providing you with peace of mind and hassle-free assistance should you need it. Please note that our mattresses cannot be returned once opened
Brand: Dyonery
Size: King
Product Dimensions: 80"L x 76"W x 14"Th
Item Firmness Description: Firm
Top Style: Tight Top
Cover Material: Cooling Knit Fabric
Number of Layers: 2
Fill Material: Memory Foam
Special Feature: Copper Memory Foam
Color: Black
Product Dimensions: 80 x 76 x 14 inches
Item Weight: 115 pounds
Manufacturer: Dyonery
Item model number: DYO-14K-BL
Date First Available: November 2, 2023
Age Range Description: Adult
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Jan 10 – Jan 11
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.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
- Klarna Financing
- Affirm Pay in 4
- Affirm Financing
- Afterpay Financing
- PayTomorrow Financing
- Financing through Apple Pay
Learn more about financing & leasing here.
Similar Products
Top Amazon Reviews
Size: Twin
Style: Firm - Gold
Updated Review: I got the twin size of this very firm 14” mattress and have been sleeping on it since October 23rd. After adding a 3” memory foam topper, it’s close to perfect. I sleep so well now that I don’t even toss and turn and wake up with no back pain. Supportive, cooling, and high-quality—highly recommend! I just received my new twin Firm-Gold mattress today and wanted to share my first impressions! For context, I’m 5’5” and close to 300 lbs, so I needed something supportive. My old mattress was a hand-me-down that had been used for years. Finding a good, affordable mattress felt impossible — like mattress stores think only the rich sleep! When it arrived I unboxed it outside on my porch (semi-closed in) and noticed no smell at all. It comes vacuum-sealed and had an extra layer of plastic — I saved that to use underneath for extra protection. I also bought a new box spring and deep cleaned my room while it decompressed. I read that firm memory foam can sag if not on a flat surface, so we cut some leftover plywood to size and put it on top of the box spring before setting the mattress down. After about 15 hours (it recommends 24, but I had nowhere else to sleep) I made the bed with Egyptian cotton sheets and my cooling blanket. The mattress itself has a built-in cooling effect, and with my blanket it felt cool and comfortable right away. When I first laid down it felt firm and supportive but still contoured to my body when I was on my side. I have chronic back pain, and surprisingly my back didn’t hurt at all — I wasn’t tossing and turning like usual. A big plus for me: the mattress has a removable cover so I can wash it — I wash everything for that fresh feel, so that feature is perfect. I also used zip ties to secure the metal frame to the box spring to prevent noise, and so far it’s totally silent. The only real issue was delivery: FedEx initially marked my property inaccessible (gate closed) even though my gate was open, my dog was secured, and I had family ready to help — my guess is the driver didn’t want to lift a 58 lb box. It was delivered the next day without issue. The bed sits a little lower than I’d like (14” mattress + 5” box spring on a short frame), but risers will fix that. Downsizing from a queen to a twin opened up my space nicely. Overall: very happy so far — firm, supportive, cool, and seems high quality. I’ll update this review in a few weeks about sagging or long-term back improvement
...
show more
Reviewed in the United States on October 24, 2025 by Jessica
Size: California King
Style: Firm - Gold
I was honestly impressed with this mattress. It came in relatively small box for a cal king, expanded quickly, and had no noticeable odor at all. It’s firmer than I expected for something that was rolled up so tight, but it’s very supportive and stays nice and cool. For just a few hundred dollars, it’s easily the most comfortable bed I’ve ever had. I might go for the medium firmness next time, but this one has actually been great for my back. Definitely a solid buy.
...
show more
Reviewed in the United States on November 3, 2025 by Sdw
Size: Queen
Style: Firm - Gold
When I tell you that this mattress is EVERYTHING, I mean it's everything!!!. I truly have hip and back problems. I've had them for years. Years of injections, Chiropractic care, and pain meds. In 8 yrs I've purchased a Serta perfect sleep,(medium firm) 1,000 dollars and a Sterns and Foster (medium firm)1,800 dollars and would be in soooooo much pain in the morning. I've never purchased a memory foam mattress before. So in March my son purchased his 3 boys a Nectar medium firm memory foam mattress from Amazon. I sat on one and thought wow, this would be great if it was more firm. I saw Nectar Medium firm mattresses at Sam's but not firm... Since Amazon had Amazon days on October 8-9, I started looking at mattresses since the prices were great. I've looked at sooooooo many then I ran across this mattress and it was 250.00 less than regularly priced. All the reviews, with the exception of one stated that it is FIRM, FIRM, and everyone LOVED it. I figured why not, 350.00 for a firm, copper gel mattress isn't that bad. I took a chance and bought it, and btw an additional 50.00 came off at the checkout. So 300.00. I ordered it on the 8th and it was supposed to be here on the 20th, 2 days later Fed Ex delivered it, Like WHAT!!!!???!!! I was super happy and excited to get it. The box was heavy, my son and grandkids brought it to the bedroom and it was packaged well. I've read it is best to open in a warm room, so I had the blinds open and the sun made my room warm. I opened it on the bed and within 10 mins it was full and exactly 14 inches It is FIRM FIRM....I have never in my life slept so good. Better than a hotel mattress. No indentations, it doesn't move when I get up, my 3 dogs jumped in and out and I didn't wake. I love the grey cover. It's well made, and hey, I'm at the change of life stage and I have NOT been hot at night, no back or hip pains in the morning, no waking in the middle of the night. To be honest, I've been sleeping in as late as two hours past the time I normally get up to let my dogs out. They have been barking to wake me up.. Hahaha... I am super happy, and satisfied with my purchase. I totally, and highly recommend this mattress..
...
show more
Reviewed in the United States on October 14, 2024 by TrishiaJj