---
product_id: 61667318
title: "Hypnia 12 inch Memory Foam Mattress, King Size 5ft x 6ft6"
brand: "hypnia"
price: "¥141399"
currency: JPY
in_stock: false
reviews_count: 3
url: https://www.desertcart.jp/products/61667318-hypnia-12-inch-memory-foam-mattress-king-size-5ft-x
store_origin: JP
region: Japan
---

# 12 inch Depth Hypoallergenic King Size 5ft x 6ft6 Hypnia 12 inch Memory Foam Mattress, King Size 5ft x 6ft6

**Brand:** hypnia
**Price:** ¥141399
**Availability:** ❌ Out of Stock

## Summary

> 🛌 Dream Big, Sleep Better!

## Quick Answers

- **What is this?** Hypnia 12 inch Memory Foam Mattress, King Size 5ft x 6ft6 by hypnia
- **How much does it cost?** ¥141399 with free shipping
- **Is it available?** Currently out of stock
- **Where can I buy it?** [www.desertcart.jp](https://www.desertcart.jp/products/61667318-hypnia-12-inch-memory-foam-mattress-king-size-5ft-x)

## Best For

- hypnia enthusiasts

## Why This Product

- Trusted hypnia brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Allergy-Friendly:** Breathe easy with hypoallergenic materials that resist dust and dust mites.
- • **Cloud-Like Comfort:** Experience the perfect balance of support and softness with 3 inches of premium memory foam.
- • **Sleep Like Royalty:** Indulge in a spacious 5ft x 6ft6 King Size mattress that transforms your sleep experience.
- • **Stay Fresh & Clean:** Enjoy a removable, washable CoolSoft cover that keeps your mattress fresh and inviting.
- • **Effortless Maintenance:** Designed for non-turn convenience, ensuring your mattress stays in top shape with minimal effort.

## Overview

The Hypnia 12 inch Memory Foam Mattress offers a luxurious King Size sleeping surface, featuring a 3-inch memory foam layer for optimal comfort. With a total depth of 12 inches and a medium-firm comfort rating, this mattress is designed to cater to diverse sleep preferences. Its removable and washable CoolSoft cover ensures cleanliness, while hypoallergenic properties make it ideal for sensitive sleepers. Plus, its non-turn design simplifies maintenance, making it a smart choice for modern living.

## Description

Product description          Originally developed by the world's leading scientists at NASA, memory foam has now been adapted to provide the ultimate mattress solution. Memory foam reacts to the warmth of your body and contours to your shape in any position, supporting the areas that need it most allowing you to drift off into deep, high quality sleep. By doing this the pressure of your weight on the mattress is spread over a larger surface area which reduces pressure points and improves blood flow. Memory Foam will always remember its original shape and return to its normal size after each excellent night’s sleep.             Box Contains          1x Hypnia Mattress 1x CoolSoft Cover

## Features

- King Size 5ft x 6ft6 / 150cm x 200cm - Total Depth: 12 inch
- Memory Foam Depth: 3 inch
- Density: 75 kg/m3 - Comfort Rating: Medium - Firm
- Includes Removable Washable CoolSoft Cover
- Hypoallergenic, Dust and Dust Mite Resistant, Non Turn

## Images

![Hypnia 12 inch Memory Foam Mattress, King Size 5ft x 6ft6 - Image 1](https://m.media-amazon.com/images/W/IMAGERENDERING_521856-T2/images/I/61mBlHN2nQL.jpg)
![Hypnia 12 inch Memory Foam Mattress, King Size 5ft x 6ft6 - Image 2](https://m.media-amazon.com/images/W/IMAGERENDERING_521856-T2/images/I/81lxm3DDkpL.jpg)

## Customer Reviews

### ⭐ 







  
  
    One Mattress, two guarantees and a poor customer service.
  

*by M***N on Reviewed in the United Kingdom 🇬🇧 on 15 September 2014*

After deciding to buy this product we had the mattress for about 8 months with no real issues. After that the centre of the mattress started to give/sink and loose its supporting strength.As the product was advertised with a 10 year guarantee I assumed it would be relatively easy for us to resolve the problem. It turns out that is not so.I am going to copy all my email correspondence to Hypnia customer services  so you can see what they asked me to do (flipping mattresses, taking photo’s and putting weights on the mattress) in order for them to process my issue further and for them to tell me at the end, that my guarantee was no longer in date just sums up these people really.If you are considering buying this or any other mattress from Hypnia I would strongly suggest looking at something else.I now have to purchase a new mattress and I am kicking myself for paying for a cheaper brand name in the first place.I do hope Amazon read this and seriously thinks about how they are advertising the product particularly the 10 year guarantee part.Apparently one part of the mattress has a 10 year guarantee (top layer) and the other part has a 12 month guarantee (base layer)???? Its one mattress with 2 guarantees!!!!!!Read the small print guys!!!!!!!!I’m sure not everyone will read the below but here it is:First email from myself:Good evening,I would like to enquire about my warranty of the mattress I purchased from yourselves via amazon on the 21/11/12 (Amazon number is above). The foam has started to compress more and more and is becoming uncomfortable and is losing its ability to support myself. As you can imagine this is quite disappointing as the mattress has been very comfortable up until the past month. Can you advise on the 10 year warranty please, as it is becoming unusable?Their response:Good Afternoon,Thank you for your email.I can see that from looking at our records, you did indeed purchase through Amazon from our authorised retailer Sleeptight Memory Foam.We are sorry to hear that you are experiencing problems with your mattress. For us to be able to proceed in the correct manner for you, can you please confirm whether you find that you are sinking into the mattress more in certain areas than others?Kind Regards...........Customer ServicesMy second email:Hi,Thanks for the prompt response. I'm sorry if I wasn't very clear. Yes, the mattress isn't as stable in the lower back area as it once was. It seems a lot less stable now than even two or three months ago.Hope this helps clarify for you. I look forward to hearing from you.Their response:Good Morning,Thank you for your email.Please can you send us some pictures describing what you are experiencing?If you are finding that you are sinking in, please send us a picture with a heavy object such as a multi-pack of baked beans or a sealed box of washing powder or something similar with definite edges in the area where this occurs, so we can see the amount you are sinking into the base. If you can also please take a couple of photos of the same item in an area where the mattress is still firm and supportive so that we have a clear comparison between the areas.Please remove any sheets and the cover that comes with the mattress so we can see the foam itself.Kind Regards,…………Customer ServicesMy Third Email:Hi apologies for the delay,Here are two pictures of the foam. One is sinking in a considerable more than the other.The recovery of the foam seems to take longer in the problem area too.Their response:Good Afternoon, Thank you for your email and photos.From viewing the photos we can see that there is a difference in the weights placed in the middle of the mattress compared to the weights placed toward the outer areas.For us to be able to ascertain where the softness may be originating from can you please flip the mattress upside down and lay across the entire surface of the base layer and come back to us with how the base layer feels, whether it is firm or soft?Please be advised that you do not need to spend an entire night on the base layer, about 5-10 minutes will suffice.Once we have that information, we can advise you further.Kind Regards……….Customer ServicesMy fourth Email:Good afternoon,Further to our telephone conversation we have flipped the mattress and layed on it for 10 minutes. the centre of the mattress was very soft with little to no support very similar to the normal side up and the head and feet end were relatively firm.I do hope this is the last request we have to perform, in order for you to progress this matter further.Their Response:Good morning,Thank you for your email and information regarding the base layer.I can confirm that from the photos and the information you have provided us with, we have deduced that it is the base layer of the mattress that is causing the issue.Unfortunately the base layer of the mattress is only covered by the manufacturers guarantee for 12 months and as you purchased this mattress in November 2012, you are unfortunately out of this period.I have included a link below for the guarantee which outline what and what is not covered by the guarantee:http://www.hypnia.com/content/171-hypnia-10-year-guaranteeIf you require any further information, please do not hesitate to contact us.Kind RegardsKayleighCustomer Services Supervisor

### ⭐⭐⭐⭐⭐ 







  
  
    Luxury comfort for a bargain price
  

*by J***E on Reviewed in the United Kingdom 🇬🇧 on 25 June 2012*

My first instinct after looking through Hypnia's mattresses on Amazon was that something didn't feel right. They were too cheap, and the reviews were too good. As if they were manufactured or even fake. But I have not known Amazon to host fake reviews and after deliberating about it, I decided to take the plunge and order the Hypnia King size 12" deep Visco mattress.It comes vacuum packed in a compact (but extremely heavy) box. The packaging is convenient for such a large product. Out of the box, it took only a matter of hours to decompress to the correct size, however I gave it about 5 days in total (Hypnia recommend 48 hours or so) as I was waiting for the bed frame to arrive. The mattress is covered in a high quality feeling cover, which looks very nice and is soft and friendly to the touch.There is one thing to bear in mind, and that is that the mattress does smell rather bad at first. The smell (a chemically fishy smell) was unpleasant and I definitely would not have liked to sleep on it for the first few days. It didn't make the room smell terrible, but lying or sitting on it, you were definitely aware of it. Thankfully by the time my frame was ready (4-5 days) the smell was mostly gone, and after a full week I would say it had vanished altogether. I cannot detect a trace of it now (nearly 2 months).I was unsure whether a memory foam mattress would really live up to the hype. The mattress feels very firm to the touch initially, but it conforms around you (subtley - you don't sink deeply in to it), supporting your body in all areas. Much more support in fact than a spring mattress can provide. This results in an unexpectedly comfortable experience. It is odd because we normally associate soft things with comfort, so to experience comfort from a mattress that initially feels so hard it odd!An added bonus were the pillows, two of which are included. They are contoured, and used the correct way around (with the thickest part at your neck), provide amazing neck support (especially for a side sleeper like myself) and a very comfortable sleep. The only down side is they are much smaller than a regular pillow, so end up lost in a normal pillow cover. Their small size also makes them unsuitable for using like bolster pillows to prop you up when reading. A 
  
Large Traditional Shape Memory Foam Pillow







  
  
     sorted that out.The only down side I can think of is that you'll have to look carefully to find fitted sheets that are deep enough to fit this mattress properly. I got some regular ones at Asda, which fit OK, but are not perfect.After 2 months of sleeping on it, I am extremely pleased and dumbfounded that I spent so little on such a good mattress. And the price is even less now than I paid! I thorougly recommend this product.

### ⭐⭐⭐⭐⭐ 







  
  
    You won't regret getting one
  

*by S***A on Reviewed in the United Kingdom 🇬🇧 on 22 December 2015*

Don't ever believe the salesman's pitch in the bed shop about spending nearly £2K for a memory foam mattress.  Save your money.  Honestly.  We suffered with a sprung mattress for years with creaky springs, having to rotate and flip over to get any shape or support.  It was also very cold.  Then we bought this mattress after buying one for our daughter.  Oh my word !!!  Warm, supportive, deep so no feeling any of the bed frame underneath.  No sound moving around or getting in or out of bed.  Doesn't need to be rotated or flipped and is resilient to bed mites.  My husband was sceptical about moving away from a traditional mattress but got desperate and we couldn't afford the bed shop prices and so he agreed to buy the mattress that our daughter had loved for ages.When it arrived it was in a box about two feet deep and six feet long.  It was quite heavy but I was able to drag it into the spare bedroom where I opened the box carefully with scissors and the mattress started to open like magic.  It had an unusual smell which we were expecting from other reviews and so left the window on the latch and the door closed.  By the morning the mattress had gained it's shape, size and left with very little smell.  First night on the bed it felt quite hard - in comparison to our other mattress though it was bliss.  After a couple of weeks it is amazingly comfortable and even if I had to buy another in four or five years time, I still wouldn't have to spend out the ridiculous amount of money in the recommended eight years they say for a standard mattress.Well worth getting out of the traditional comfort zone for and entering the new age of sleeping !!  Save your pounds !!

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*Product available on Desertcart Japan*
*Store origin: JP*
*Last updated: 2026-02-18*