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Slumber Castle

King Size Mattress, 12 Inch Hybrid King Mattress in a Box, Gel Memory Foam and Pocket Coils Innerpring Mattresses with Ergonomic Design, Cooler Sleep with Pressure Relief and Support, 76"*80"*12"

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Availability: Only 5 left in stock, order soon!
Fulfilled by Slumber Castle Direct
Arrives Monday, Aug 17
Order within 1 hour and 43 seconds
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Size: King


Style: 12 Inch


Features

  • Hybrid King size Mattress Slumber Castle King mattress (80" x 76" x 12"),featuring individual pocket springs combined with luxury slow spring back foam. Ergonomic designed to relieve pressure -feet, legs, hips, waist.shoulders, neck,and head-for a cosy dream
  • Breathable & Skin-FriendlyThe 12-inch king mattress is CertiPUR-US certified and Oeko-Tex Standard 100 certified, ensuring that its materials are safe and non-toxic. Medium Firm Feel and Ergonomic design ensuring sufficient support and pressure relief
  • Medium Firm Feel King MattressWith a medium-firm feel and an advanced pocket spring system, this 12 inch king mattress minimizes motion transfer and provides consistent support from every angle
  • Motion Isolation & Edge SupportIndividually Wrapped Coils with Motion Isolation, the king size mattresses effectively isolates motion. Enjoy a peaceful night's sleep with our hybrid mattress and you wont be disturbed by creaking or squeaking sounds
  • Mattress in a box & Easy to set upPerfect for all bed frames. Bed in a box for convenient transport. Upon receipt the king size mattress, Please allow 24-72 hours for your hybrid mattress to expand to the original size, then you can cosy into a dream
  • 101-day trial periodEach Slumber Castle innerspring mattress comes with a 101-night free sleep trial. If you have any questions, Our customer support is available 24/7 to assist you. (Go to Your Orders > Get Help with Order > Ask Product Question)

Brand: Slumber Castle


Size: King


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


Item Weight: 95 Pounds


Item Firmness Description: Medium Firm


Top Style: Euro Top


Cover Material: Polyester


Number of Layers: 2


Fill Material: Gel Memory Foam, High Density Foam


Special Feature: Breathable, Edge Support, Innerspring Hybrid Mattress, Medium-Firm plush feel, Motion Isolation


Item Firmness Description: Medium Firm


Number of Layers: 2


Additional Features: Breathable, Edge Support, Innerspring Hybrid Mattress, Medium-Firm plush feel, Motion Isolation


Mattress Coil Type: Pocketed Coil


Construction Type: Hybrid


Number of Mattress Coils: 850


Is Customizable?: No


Portable: Yes


Is Foldable: No


Size: King


Item Dimensions L x W x Thickness: 80"L x 76"W x 12"Th


Item Weight: 95 Pounds


Item Depth: 12 inches


Item Dimensions: 80 x 76 x 12 inches


top-style: Euro Top


Color: Royal Blue


Style Name: 12 Inch


Brand Name: Slumber Castle


Age Range Description: All Ages


Model Name: SC King Hybrid MF


Product Benefits: Full Body Support, Keeping Cool, Motion Isolation, Release Pressure, Strong Edge Support


Model Number: SC-King-Hybrid-MF


Manufacturer: Slumber Castle


Cover Material: Polyester


Fill Material: Gel Memory Foam, High Density Foam


Product Care Instructions: Avoid excessive pressure and jumping, Clean with a dry cloth moistened with water, Cycle Gently, Keep dry and ventilated, Rotate and turn regularly, Use a mattress protector


Mattress Comfort Layer Material: Gel Memory Foam


Material Type: Gel Memory Foam, High Density Foam


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, Aug 17

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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Top Amazon Reviews

    • Incredible Comfort & Support — Best Sleep I’ve Had in Years!
I was honestly surprised by how good this mattress is, especially for the price. It arrived quickly, was easy to unbox, and expanded to the full 12 inches within a few hours. The moment I laid down, I could feel the difference — the combination of memory foam and individually wrapped springs gives the perfect balance of softness and support. The memory foam contours to my body without sinking too much, while the pocket springs keep everything lifted and aligned. I wake up without the back and hip pain I used to feel with my old mattress. It also sleeps really cool — the breathable design keeps me from overheating during the night, which has always been a problem for me. I love that it’s CertiPUR-US certified too. It feels safe, clean, and well-made. For a mattress that comes compressed in a box, the quality is honestly amazing. If you’re looking for a queen mattress that delivers comfort, support, and real pressure relief, this one is a total win. I’m sleeping better than I have in a long time. Highly recommend! ... show more
Reviewed in the United States on December 11, 2025 by Milissa Sprinkle
    • comfortable, great value
Size: Queen Style: 12 Inch
VERY PLEASED!!! Great mattress for the money. Helps alleviate back pain, fully ready in about 20hrs. I slept amazing. great buy, great value! 10/10 would definitely buy again.
Reviewed in the United States on March 24, 2026 by Mason foster
    • It's so comfortable
Size: Full Style: 14 Inch
This is the best bed I've ever had so plush and sooo big
Reviewed in the United States on March 1, 2026 by Amazon Customer
    • I'm just as surprised as you are by this rating....
To be honest, I had tried a Beautyrest Black Series 4 Ultra Plush Medium firm mattress in-store and it stole my heart, and then the price tag broke it again. So I came on Amazon to try and find something "like" that one, which also seemed expensive. And then I gave up and said to myself "meh, you're sleeping on basically a wooden piece of plywood right now because your futon mattress is doing nothing, anything is better than this", so I decided on this cheap hybrid mattress. But let me tell you something, the price was cheap but the quality was not! Now, I'm not saying this thing is luxurious, no....it's no Beautyrest Black Ultra Plush Series 4 (yes, that is an slight air of resentment in my voice), no....but it is still really good actually. I have chronic lower back pain and, even taking sleeping pills, last night was the first time I've been comfortable enough laying in bed to sleep through the whole night (a whole 5 & 1/2 hours - which is really good for chronic pain sufferers). On a scale of "sleeping on gravel rocks" to "luxury spa hotel cloud mattress of my dreams", this one gets a solid "it does what a mattress is supposed to do". For the "surprisingly satisfactory" quality at the way cheap "can't actually be a quality mattress" price that I bought it for, I'm giving it 5 stars. It really exceeded my expectations. P.S. - in case it makes a difference to anybody, my dog didn't get up and walk around the bed to change positions even once after we got comfortable last night, but she was annoyingly energetic this morning, so....you win some, you lose some 🤷♀️ ... show more
Reviewed in the United States on December 23, 2025 by Gretchen M.
    • Good Value
This is not bad for the price. The bed is comfortable. It is very soft so if firm is what you want this is not it.
Reviewed in the United States on November 19, 2025 by Rhonda Weber
    • Fantastic Mattress
Size: King Style: 12 Inch
This is hands down the best and most comfortable mattress I have ever slept. I will never again buy anything but a foam mattress. Fast shipping and easy to get on the bed.
Reviewed in the United States on February 25, 2026 by Thomas T
    • TERRIBLE! Terrible mattress!
I am so disappointed in this mattress. It came quickly, which I appreciate however it’s just so strange a mattress. Yes when you lay on it, it is firm, a little too firm for my liking, but that is not the issue really. The issue is that the sides of the mattress breakdown very easily and are very weak. Even though it’s a pretty firm mattress, it is strangely bouncy and when sleeping on the mattress you can literally feel the springs beneath you. I would love to return this item if it weren’t for the fact that you can’t roll it back up and put it back in the box. I most definitely would not purchase this mattress again or recommend purchasing it. I give the one star mostly because I don’t have another option but the shipping time alone earns the first star. ... show more
Reviewed in the United States on December 22, 2025 by April Goosby
    • Just get it girl.💞
Size: Queen Style: 12 Inch
The media could not be loaded. omggggg. First I’m not cheap but I just moved In into a bigger apartment and decided that I need a new bed. This bed is medium firm but so soft when you sit on it. It came in a box that was easy to take out but watch out on how you open when you’re taking out the plastic wrap . it’s pretty true to size since my room is pretty big and a takes up a nice corner. 10/10 would recommend if you’re looking for a cheap bed that’s under $200 because I think overall I paid 149 because of the shipping but somethings take a little bit more money but it’s so worth it. Plus no fiber glass , idk why that’s even a thing to be honest . ... show more
Reviewed in the United States on February 7, 2026 by Sophie mar

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