# Sunny Heart MAT12 King 8-Inch Medium-Firm Gel Memory Foam Mattress

Medium-Firm: Sunny Heart MAT12 is an 8-inch king memory foam mattress listed as medium firm, with gel memory foam and a high-density foam core. Its boxed, unroll-to-set-up format and removable cover are practical features, while the listing contains inconsistent model and package details worth checking before purchase.

- [Original product page](https://best-deals.pro/product/sunny-heart-mat12-king-8-inch-gel-memory-foam-mattress)
- [View offer](https://best-deals.pro/visit/sunny-heart-mat12-king-8-inch-gel-memory-foam-mattress)
- Market: US
- Language: en-US
- Currency: USD
- Brand: Sunny Heart
- Model: MAT12
- Category: Home & Kitchen > Furniture > Mattresses
- Price: 178.48 USD
- Previous price: 209.99 USD
- Discount: 15%
- Price checked: 2026-11-14T06:28:30.741Z
- Rating: 4.8 / 5
- Reviews: 49

Prices and deal status are the latest recorded data, not a guarantee of availability. Confirm the price and availability with the store.

## At a glance

- The listing describes gel memory foam over a high-density foam core, with medium-firm feel.
- The cover is described as removable and machine washable in the feature text.
- The mattress ships compressed in a box. The listing says to allow 24–72 hours to regain its intended shape, loft, and feel.

## Pros

- King size and an 8-inch profile suit buyers seeking a thinner foam mattress.
- A removable, machine-washable zippered cover can make cleaning more convenient, according to the listing.
- The box format and unroll setup avoid carrying a fully expanded mattress through the home.

## Cons

- An 8-inch profile may not suit buyers seeking a thicker mattress.

## Specifications

### Identity
- Brand: Sunny Heart
- Model: MAT12
- Size: King
- Mattress type: Memory Foam
### Dimensions and installation
- Dimensions listed: 80 x 8 x 76 inches
- Thickness: 8 inches
- Weight listed: 52.9 pounds
### Construction and feel
- Firmness: Medium Firm
- Top style: Euro Top
- Number of layers: 1
- Fill material: Gel Memory Foam, High Density Foam
- Cover material: Polyester
- Color: White
### Features and capacity
- Additional features: Breathable, Pressure Relief, Removable Cover
- Weight limit: 1200 pounds

## Before you buy

- Listing details conflict or remain unconfirmed: the model is MAT12 in the model fields but the manufacturer part number is MAT20, and the stated dimensions appear in differing orders, including 80"L x 8"W x 76"Th. The feature text describes a soft mattress while the specification says Medium Firm. The explicit contents list says Memory Foam, while a separate highlight claims a mattress with a removable fiberglass-free cover and certification. Verify the selected listing's dimensions, feel, exact model and included items. The listing also says expansion takes 24–72 hours.

## In the box

- Memory Foam (Included)
- Removable fiberglass-free cover and mattress (Check selected pack): A product highlight claims these items, but the explicit contents list names only Memory Foam. Check the selected listing.

## A good fit for

- King-bed shoppers looking for an 8-inch memory foam mattress with a listed medium-firm feel.
- Buyers who prefer a mattress delivered compressed and can allow time for it to expand.

## Less suited to

- Shoppers who need a firmly confirmed model number, exact dimensions or package inventory before ordering.
- Buyers seeking a thicker mattress or a feel other than the listed medium-firm option.

## Customer feedback

Customer feedback highlights comfort and firmness, and some buyers describe the mattress as good value. Those impressions may matter to shoppers considering its listed medium-firm feel, but the available feedback does not establish that it will suit every sleeper or verify the product specifications. The overall rating distribution is mostly five-star, with some three-star ratings, and the sample is limited.
- Positive themes: Customers describe the mattress as comfortable.
- Positive themes: Customers appreciate its firmness.
- Positive themes: Customers mention value for money.

## Frequently asked questions

### What size and thickness is this mattress listed as?
It is listed as King and 8 inches thick. The dimensions fields are inconsistent in how they order the measurements, so confirm them in the selected listing.
### What is the listed firmness?
The specification lists Medium Firm, although feature copy calls the mattress soft. The actual feel is not independently established, so check the product listing if firmness is important to you.
### How long should it take to expand after unboxing?
The listing says to allow 24–72 hours for it to regain its intended shape, loft, and feel.
### Is the cover removable and washable?
The feature text describes a removable, machine-washable zippered cover. The exact included cover details should be confirmed because the package information is inconsistent.

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## Images

![Sunny Heart MAT12 King 8-Inch Medium-Firm Gel Memory Foam Mattress — 1](https://best-deals.pro/i/7rFJ-kg0e8C6vLcMw8yScBaSIgExdRYJEJ37CD9S3LUm82R254VHv53qoPkrqLKJRZrpnotDMOJB1Uy0-lhKs4JwMao9MCav2mhozPd6QDBfe79DTDgYQ7HN.jpg)

![Sunny Heart MAT12 King 8-Inch Medium-Firm Gel Memory Foam Mattress — 2](https://best-deals.pro/i/8xVB_Fkki4mJ27mpR7MeOYqKR-ijcHVeaEv-CUy2SKVR8oVrilM_RyKUHVwcfT21mhispm6R0MLXavyi3RwBzAOk_YxS4yS8GUdiH495JyzcjOXfIYMv9ZcN.jpg)

![Sunny Heart MAT12 King 8-Inch Medium-Firm Gel Memory Foam Mattress — 3](https://best-deals.pro/i/OfzqDtD5OOh-UmI3TOUbr_jEbB9hnKZ2G0tWqFmzZxnLgs1dvkJoz04AKLiY1KXKF4jB0-FoXjhX0VcWVre8E6BAgIHReRv-RjqLSZS8BalUp8BntSpNj_bO.jpg)

![Sunny Heart MAT12 King 8-Inch Medium-Firm Gel Memory Foam Mattress — 4](https://best-deals.pro/i/WWK_ww8YCixcEr8fMA7Odt80PGmp1YEoWNhFMQMAsCZAM7CAnl26bluZy2BHIAXkgyhni6mWpoa6OCMqqBT3IcacXRDl511TKEJNWhZZDqWqwaYpb0eCy7GC.jpg)

![Sunny Heart MAT12 King 8-Inch Medium-Firm Gel Memory Foam Mattress — 5](https://best-deals.pro/i/e-w0WYvqSVoU5sI2t3iCz3i-jwR_-ASU8eAnfMysuAvNEpJV-qm_UORFH-_UEFKhFGb8ZD84faWPP9Mre6vgdh1NvB7k3wwsFB_77OMUBj3LH3zjCbSKWUD8.jpg)

![Sunny Heart MAT12 King 8-Inch Medium-Firm Gel Memory Foam Mattress — 6](https://best-deals.pro/i/zNVQ7pJBysrRSI_j1wk4IREKGdLVJFK7FzyC5LOMuht43NW7X4uswN44GMG1FaBho5BVp3g7lQyzCg68GzDpjAg1kbO50fH2kdVqfZDzk9oQmVPump_pWPku.jpg)

![Sunny Heart MAT12 King 8-Inch Medium-Firm Gel Memory Foam Mattress — 7](https://best-deals.pro/i/CJ6Y82-thlLjLQbWpW_A8ziFBm-JOmQrFk8UTW0m0-ebGboUSzBVnA0-85oYpZH3ccA_SAKiaYwMU35dBLxjMfHHR2JRR8Vh0XmtgMPdvCxnNVA1vjvFkpws.jpg)