# SLEEP100 SYN3333042 King 14-Inch Medium-Firm Hybrid Mattress

Medium-Firm: The SLEEP100 SYN3333042 is a 14-inch King hybrid mattress listed as medium firm, with pocket coils, foam comfort layers and a Euro top. Its listed 5-zone support, breathable cover, motion isolation and fiberglass-free construction are manufacturer claims, while customer feedback reports varied experiences with fit.

- [Original product page](https://best-deals.pro/product/sleep100-syn3333042-king-medium-firm-hybrid-mattress)
- [View offer](https://best-deals.pro/visit/sleep100-syn3333042-king-medium-firm-hybrid-mattress)
- Market: US
- Language: en-US
- Currency: USD
- Brand: SLEEP100
- Model: SYN3333042
- Category: Home & Kitchen > Furniture > Mattresses
- Price: 299.99 USD
- Previous price: 351.49 USD
- Discount: 15%
- Price checked: 2026-11-14T09:39:04.113Z
- Rating: 4.4 / 5
- Reviews: 1374

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 targeted 5-zone support for the lower back, shoulders and hips.
- Pocket springs and foam are claimed to combine responsive support with reduced motion transfer.
- The breathable cover and open pocket-spring construction are described as promoting airflow.
- The listing claims fiberglass-free materials and a 365-night home trial, plus a 10-year limited warranty.
- Compressed into a box for delivery and setup, according to the listing.

## Pros

- King dimensions and 14-inch thickness are clearly specified.
- The hybrid design combines pocketed coils with a gel-memory-foam comfort layer.
- A 365-night trial and 10-year limited warranty are stated in the listing.

## Specifications

### Identity
- Brand: SLEEP100
- Model: SYN3333042
- Size: King
- Mattress type: Hybrid
- Firmness: Medium Firm
### Dimensions and installation
- Dimensions listed: 80 x 76 x 14 inches
- Weight listed: 102 pounds
- Thickness: 14 inches
### Construction and materials
- Top style: Euro Top
- Coil type: Pocketed Coil
- Number of coils: 384
- Number of layers: 2
- Comfort layer material: Gel Memory Foam
- Fill material: Cotton
- Cover material: Polyester Blend
- Material type: Cotton Blend
- Color: Grey
### Capacity and features
- Weight capacity: 800 pounds
- Additional feature: Breathable

## Before you buy

- The listing identifies the mattress as both cotton-filled and gel-memory-foam comfort layered, and calls its material type a cotton blend. It also lists a 2-layer construction alongside multiple foam and spring elements without explaining the layer breakdown. The title claims fiberglass-free materials and a 365-night trial, while the warranty text specifies a 10-year limited warranty. Confirm material composition, trial terms and warranty conditions for the selected listing.

## In the box

- Mattress (Included)

## A good fit for

- King-bed shoppers seeking a 14-inch hybrid with a medium-firm label and pocket coils.
- Couples interested in the listing's claimed motion isolation and reinforced edge support.
- Back or combination sleepers considering the advertised 5-zone support design.

## Less suited to

- Shoppers who need independently established evidence of cooling, pressure relief or motion isolation.
- Buyers who require fully detailed material and layer specifications before choosing.

## Customer feedback

Customer feedback describes the mattress as comfortable and supportive, with favorable reports about firmness, back comfort, sleep quality and setup. Some customers say the fit works well on their bed frame, while others report sheets sliding around. That mixed fit feedback matters for bedding compatibility. These are customer perceptions and do not independently establish the advertised support or motion-isolation performance.
- Positive themes: Customers report comfort and a firmness they appreciate.
- Positive themes: Feedback mentions support, improved sleep quality and easier setup.
- Mixed feedback: Fit feedback is mixed. Some report a good fit on their frame, while others mention sheets sliding around.

## Frequently asked questions

### What firmness is listed for this mattress?
It is listed as medium firm. The page notes that perceived firmness can vary with body weight and sleep style.
### What is the mattress made with?
The listing names pocket coils, a gel-memory-foam comfort layer, cotton fill and a polyester-blend cover. It also calls the material type a cotton blend, so the full material and layer composition is not clearly reconciled.
### What trial and warranty are stated?
The listing claims a 365-night home trial and a 10-year limited warranty. Check the selected listing for the applicable terms.
### Does the listing state fiberglass-free construction?
Yes. The title and listing text claim fiberglass-free materials. This is a listing claim, not an independently verified material assessment.

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## Images

![SLEEP100 SYN3333042 King 14-Inch Medium-Firm Hybrid Mattress — 1](https://best-deals.pro/i/sAg3lKLABZxkQ4USymZW0oCGkQqSJCb6eyaq1B3dcz6xTKmnSBuKEHslJrzfavD4nXAgVo3BMV89ENrDfugVQ3spkg-F-SWcXGa6glLEVJsZKcBqJo0Ybjtx.jpg)

![SLEEP100 SYN3333042 King 14-Inch Medium-Firm Hybrid Mattress — 2](https://best-deals.pro/i/wi-dnfQGPQCSgPrSmdsuDfkeEpxE6NNAm_C3m-041bjL9m0eYnDXWT9lU506I9bpKdortp2k0ILWrjZGtD6PQCpZ8sSV1s08oNlA5OYVqYeLIE-_Nvr1IM4P.jpg)

![SLEEP100 SYN3333042 King 14-Inch Medium-Firm Hybrid Mattress — 3](https://best-deals.pro/i/yo-RE6MpF2zCvl8mY9Vg1FQCMdvJSxnsARtlNa5tMHzzKq7-m1R5koMacw4F3pp5jUnrFInqm3c3Z3_NNWJB-u90-eeO60eTnpJvotkGjWjymwFoiFj0ucV8.jpg)

![SLEEP100 SYN3333042 King 14-Inch Medium-Firm Hybrid Mattress — 4](https://best-deals.pro/i/wiqZHZy3VXWh34gnL8SARDrIQOfFUjBxWT-fB5S5_DRb8TpP-kPY8K81AgV9RkBJndkQljbKf0mswJ15Lpj6ywotQZxZVkm6crTao3Z-JB-ZnEgcCOIRiTo6.jpg)

![SLEEP100 SYN3333042 King 14-Inch Medium-Firm Hybrid Mattress — 5](https://best-deals.pro/i/mSysPGNvrLTsVPjLCOK87VEGoR5jyRVpN87EUh6wGleeuKw4sF32nUGhX0bSZIxmMnXdvAjwmEspBT0C54VkxtQjm4rcoICM97D7GScOwt4X8Pmk7pnjef2m.jpg)

![SLEEP100 SYN3333042 King 14-Inch Medium-Firm Hybrid Mattress — 6](https://best-deals.pro/i/CSmFS5ClZ-gn5KUPQJ3tFlVNfNFgpCoqkNf1YtJZoOWvbs3aJAavQSvWqCvvVGVXU9Dgygl2JZuosKuHksuvtGvew9PRX_yx0J8zNrQvr1mUTZ5Cz20Bn2W6.jpg)

![SLEEP100 SYN3333042 King 14-Inch Medium-Firm Hybrid Mattress — 7](https://best-deals.pro/i/ucMnYulN8kxnF_c1CXDpPvdm6mRGR8mcuFOTzRO8rLzAn1YsdToacPkvbDNxJrCEHmiWe5ZDkII6_fOyIIw5Mc_AnPUKT6AxOWuWkIlPvl8FpjHidOiJ_hRJ.jpg)