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Firm King Mattress – 14 Inch Memory Foam Mattress for Spinal Alignment

Based on 32 reviews
Condition: New
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$499.99
Save $100.00 was $599.99

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Availability: Unavailable
Fulfilled by SLEEP100 SYNERGY LIMITED

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At a glance

Condition
New
Color
White & Black
Size
King
Set
14" Luxe Firm
Model
P2503485
Dimensions
80 x 76 x 14 in
Weight
82.8 lb
In the box
Mattress*1Opening Tool*1

Features 5

  • FIRM, STABLE SUPPORT FOR RESTORATIVE SLEEPWake up feeling more supported with a firm mattress designed to minimize excessive sinkage and keep your body on an even, stable surface. Responsive comfort foam gently adapts to your shape, while the high-density support core helps distribute body weight and support the lower back, hips, shoulders, and neck. Ideal for sleepers who prefer a sturdier feel and need reliable, all-night support for everyday comfort.
  • GEL MEMORY FOAM WITH COOLING COMFORTGel-infused memory foam and a breathable knit cover promote airflow to help reduce heat buildup throughout the night. The softly quilted surface creates a cooler, fresher, and more comfortable sleep environment for a more restful nights sleep.
  • MOTION ISOLATION FOR UNDISTURBED SLEEPBy contouring to your body and absorbing movement at its source, this memory foam mattress helps reduce motion transfer across the sleep surface. The spring-free design creates a stable, quiet sleep space for more restful, undisturbed nightsideal for couples and light sleepers.
  • CERTIFIED SAFE MATERIALSYour health is our priority! Sleep with greater peace of mind on a fiberglass-free mattress made with CertiPUR-US certified foam and OEKO-TEX tested fabric. Crafted without harmful substances or heavy metals, this memory foam mattress creates a cleaner, more comfortable sleep environment for everyday rest.

Description

1.How firm is this mattress? Balanced comfort; firmness varies by weight and sleep style. Under 130 lb may feel firmer; 130–230 lb get cushioning; over 230 lb feel contouring. Back sleepers notice even alignment, side sleepers more cushioning, stomach sleepers flatter. 2.Which thickness should I choose — 10", 12", or 14"? It depends on how you’ll use the mattress. 10" suits guest rooms, dorms, small spaces or budgets. 12" is most popular for daily sleep and couples. 14" feels premium with extra cushioning for bedrooms or adjustable frames. Unsure? Most start with 12". 3.What type of bed frames does this mattress work with? This mattress is compatible with platform beds, slatted frames with proper spacing, adjustable bed frames, and solid foundations. 4.How long does a foam mattress usually last, and when should I replace it or add a topper? Most quality foam mattresses on a supportive frame stay comfortable 7–10 years, depending on use and body weight. If it feels supportive but less plush, a 2–3 inch topper can refresh the surface. Deep sagging or uneven support means replacement. 5.How long does it take to fully expand after opening? Most mattresses fully expand within 2-12 hours.Cold weather can slow expansion, so let the sealed box warm indoors before opening. After unboxing, ventilate the room and allow extra time for foam to regain its shape and feel.

Specs 30

Brand SLEEP100
Size King
Product Dimensions 80"L x 76"W x 14"Th
Item Weight 82.8 pounds
Item Firmness Description Firm
Top Style Tight Top
Cover Material Polyester
Fill Material Gel Memory Foam, High Density Foam, Memory Foam

Frequently asked questions

This product is currently out of stock. Please check back later for shipping info.

Yes, absolutely! You may return this product for a full refund within 90 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


Overall, I’m happy with it and think it’s a good mattress for the price!
I’m really happy with this 12-inch firm twin memory foam mattress. Just feeling it with your hand, it feels soft and comfortable, but once you actually lay down on it, it feels much firmer. I think it definitely needs some time to break in and soften up. It has good support and a nice thick feel. Overall, I’m happy with it and think it’s a good mattress for the price! ... show more
Reviewed in the United States on August 30, 2026 by Shopping fanatic

Firm mattress as desired. No sinking occurs.
Color: White & Black Size: Queen Set name: 14" Luxe Extra Firm
We are all set up on this new mattress; it is comfortable and meets or exceeds my expectations. I hope you will enjoy yours as much as I enjoy mine.
Reviewed in the United States on August 26, 2026 by Johnny Douglas

Best mattress I've ever owned
Color: White & Black Size: Queen Set name: 14" Luxe Extra Firm
Best money ever spent. This Mattress is very firm yet comfortable no sinking, best nite sleep I've had in a long time. Love love love this mattress, definitely recommend it 100Xs over.
Reviewed in the United States on August 17, 2026 by Maria Abdelhamid

Firm
Color: White & Black Size: Queen Set name: 14" Luxe Extra Firm
Really firm. I love it
Reviewed in the United States on August 24, 2026 by Luz

great so far...!!!
Color: White & Black Size: Queen Set name: 10" Core Firm
5 stars so far...!!! very firm for me without being hard... i use a similar 10 inch at my family's house and wanted one for my house... i have disabling back issues and firm is best for me...
Reviewed in the United States on August 5, 2026 by Daisy

10/10!
Color: White & Black Size: King Set name: 14" Luxe Firm
One of our recent airbnbs had this bed, and we bought it before we even returned home we loved it so much! We used our new mattress last night for the first time and it was the best sleep we've both had in a long time! 10/10!!!
Reviewed in the United States on September 2, 2026 by Amazon Customer

Pleasantly surprised!! GREAT MATTRESS!
This mattress is simply amazing! We purchased two twin XL’s to go on our king bed. We were pleasantly surprised at how firm and supportive the mattresses are. At first when I opened them up I was skeptical because they were soft feeling, but after several hours, they firm right up. I would recommend these to anyone looking for a great support mattress that is comfortable. ... show more
Reviewed in the United States on August 28, 2026 by Wayburn M.

Best Mattress
Color: White & Black Size: Queen Set name: 12" Luxe Extra Firm
At first I was a little skeptical about this mattress and I was afraid it’s going to be too hard. I have suffered from back pains and sciatica for years. Turn out to be that this is the best mattress I’ve ever purchased. I sleep good and no aches when I wake up. I’m going to purchase another one for my in laws. ... show more
Reviewed in the United States on August 23, 2026 by JD
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