---
product_id: 791890698
title: "Duchessz 12\" Twin Size Mattress in a Box - Medium Firm Gel Memory Foam Hybrid with Pocket Springs for Maximum Support & Pressure Relief"
brand: "duchessz"
price: "¥142354"
currency: JPY
in_stock: true
reviews_count: 8
category: "Duchessz"
url: https://www.desertcart.jp/products/791890698-duchessz-12-twin-size-mattress-in-a-box-medium-firm
store_origin: JP
region: Japan
---

# Gel memory foam for cooling 12-inch hybrid thickness 10-year durability warranty Duchessz 12" Twin Size Mattress in a Box - Medium Firm Gel Memory Foam Hybrid with Pocket Springs for Maximum Support & Pressure Relief

**Brand:** duchessz
**Price:** ¥142354
**Availability:** ✅ In Stock

## Summary

> 🛏️ Elevate your sleep game with Duchessz: where comfort meets cutting-edge support.

## Quick Answers

- **What is this?** Duchessz 12" Twin Size Mattress in a Box - Medium Firm Gel Memory Foam Hybrid with Pocket Springs for Maximum Support & Pressure Relief by duchessz
- **How much does it cost?** ¥142354 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.jp](https://www.desertcart.jp/products/791890698-duchessz-12-twin-size-mattress-in-a-box-medium-firm)

## Best For

- duchessz enthusiasts

## Why This Product

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

## Key Features

- • **Certified Safe & Durable:** CertiPUR-US foams + decade-long warranty = sleep investment secured.
- • **365-Night Risk-Free Trial:** Sleep on cloud confidence for a full year—no risk, all reward.
- • **All-Sleep-Position Support:** Adaptive hybrid design cradles every sleep style flawlessly.
- • **Targeted Zoned Support System:** Precision lumbar & hip reinforcement for pain-free mornings.
- • **Motion Isolation & Edge Support:** Sleep undisturbed with zero partner bounce and 15% more usable surface.

## Overview

The Duchessz 12" Twin Size Mattress in a Box is a medium-firm hybrid combining cooling gel memory foam with individually wrapped pocket springs. Designed for all sleep positions, it features zoned lumbar support, motion isolation, and reinforced edges to maximize comfort and durability. Certified safe and backed by a 10-year warranty, it offers a 365-night risk-free trial, making it a smart, long-term sleep upgrade.

## Description

Duchessz Hybrid Mattress combines the contouring pressure relief of gel memory foam with the responsive support of individually pocketed coils, offering a balanced sleep surface that cradles without the deep sink of all-foam beds. Key Features: Dual Cooling System: Copper-infused gel foam draws heat away, paired with a breathable cover for enhanced airflow Zoned Edge Support: Reinforced perimeter reduces roll-off and increases usable sleep surface by approx. 15% Motion Isolation: Individually wrapped coils minimize partner disturbance—ideal for light sleepers Easy Care: Removable, machine-washable cover simplifies cleaning What's Included: 1× Hybrid Mattress (compressed in box) 1× Care Instructions 1× Warranty Registration Card Note: Allow 48–72 hours for full expansion. Initial off-gassing odor is normal and should dissipate within 24 hours.*

Review: Worth the money! Well made, supportive, comfortable mattress. - Great mattress! I purchased two of the 14 inch twin size and they are wonderful. My kids love them. The package arrived almost three full days early, so that was a wonderful surprise. The packaging was great, no damage at all. They were heavy but my son lifted and moved it all for me, I'm sure I could have done it on my own but he was there and didn't mind helping me. The shrink wrapping of the mattress was very nicely done and it took no time at all to "pop up" after opening them. They came with an envelope type opener that slit it without damaging the mattress. In less than 4 hours they were fully popped up to the 14 inches. They fit snug in the frame, and I appreciated that. My boys love them and sleep in their beds with smiles. I will definitely purchase again when we need a mattress. Great price. The memory foam and support is nice, soft but still offers nice support. My kids tend to sleep warm and they were comfortable with the heat level so that was another plus. Nice material, I really like the black rather than the traditional white. Nicely made / sewn. No complaints here. I will upload pictures to add to this in case it's helpful to you.
Review: Comfy, tall, good quality - This arrived earlier than expected. It's quite comfortable and bouncy. I only gave it about 60 hours to fluff up though, didn't really have a funky smell other than "new carpet/fabric". I hit it with some smelly good spray just because though. It did reach the full 14inches but my 14in pocket sheets didn't quite fit. That could be a sheet problem though. It fit a twin frame perfectly and was fun to watch decompress. Should have gotten a video :( You can feel the springs around the edges when putting the sheets on but not while sleeping. I don't have any back or hip pain and sleep on my side and back. It's actually more comfortable that the Purple mattress in the other bedroom. Great quality for a mattress in a box!

## Features

- 365-Night Risk-Free Trial — Experience our industry-leading home trial — sleep on your mattress for a full year with no risk. If it’s not the perfect fit, we’re here to help. Your satisfaction is our promise.
- All-Sleep-Position Support — Whether you sleep on your side, back, or stomach, our hybrid design adapts to you. A plush comfort layer cradles your body, while responsive pocket coils maintain natural spinal alignment all night long.
- Targeted Zoned Support System — Extra reinforcement in the lumbar and hip areas provides crucial support where you need it most. Our zoned coils and high-density foam reduce sinkage, promote healthy posture, and help ease back pain.
- Motion Isolation & Edge Support — Individually wrapped coils absorb movement, so you and your partner sleep undisturbed. Strong reinforced edges prevent sagging, expand your usable sleep surface, and ensure lasting stability.
- Certified Safe & Durable — All foams are CertiPUR-US certified for safety, performance, and durability. Backed by a 10-year warranty, this mattress is made to last. Simply unbox, allow 72 hours to fully expand, and enjoy.

## Technical Specifications

| Specification | Value |
|---------------|-------|
| Best Sellers Rank | #1,355,775 in Home & Kitchen ( See Top 100 in Home & Kitchen ) #1,864 in Mattresses |
| Brand | Duchessz |
| Customer Reviews | 4.1 out of 5 stars 57 Reviews |
| Item Firmness Description | Medium Firm |
| Item Weight | 50 Pounds |
| Product Dimensions | 80"L x 60"W x 12"Th |
| Size | Twin |
| Top Style | Euro Top |

## Product Details

- **Brand:** Duchessz
- **Size:** Twin
- **Product Dimensions:** 80"L x 60"W x 12"Th
- **Item Weight:** 50 Pounds
- **Item Firmness Description:** Medium Firm
- **Top Style:** Euro Top
- **Fill Material:** High Density Foam
- **Color:** Grey
- **Model Name:** Z3-TM
- **Construction Type:** Hybrid

## Images

![Duchessz 12" Twin Size Mattress in a Box - Medium Firm Gel Memory Foam Hybrid with Pocket Springs for Maximum Support & Pressure Relief - Image 1](https://m.media-amazon.com/images/I/71BzziTaCYL.jpg)
![Duchessz 12" Twin Size Mattress in a Box - Medium Firm Gel Memory Foam Hybrid with Pocket Springs for Maximum Support & Pressure Relief - Image 2](https://m.media-amazon.com/images/I/71mLDlZ5wmL.jpg)
![Duchessz 12" Twin Size Mattress in a Box - Medium Firm Gel Memory Foam Hybrid with Pocket Springs for Maximum Support & Pressure Relief - Image 3](https://m.media-amazon.com/images/I/8100KlZ5KHL.jpg)
![Duchessz 12" Twin Size Mattress in a Box - Medium Firm Gel Memory Foam Hybrid with Pocket Springs for Maximum Support & Pressure Relief - Image 4](https://m.media-amazon.com/images/I/81XJtuJuWaL.jpg)
![Duchessz 12" Twin Size Mattress in a Box - Medium Firm Gel Memory Foam Hybrid with Pocket Springs for Maximum Support & Pressure Relief - Image 5](https://m.media-amazon.com/images/I/81tK-hXYfDL.jpg)

## Available Options

This product comes in different **Size, Style** options.

## Customer Reviews

### ⭐⭐⭐⭐⭐ Worth the money! Well made, supportive, comfortable mattress.
*by K***S on September 22, 2025*

Great mattress! I purchased two of the 14 inch twin size and they are wonderful. My kids love them. The package arrived almost three full days early, so that was a wonderful surprise. The packaging was great, no damage at all. They were heavy but my son lifted and moved it all for me, I'm sure I could have done it on my own but he was there and didn't mind helping me. The shrink wrapping of the mattress was very nicely done and it took no time at all to "pop up" after opening them. They came with an envelope type opener that slit it without damaging the mattress. In less than 4 hours they were fully popped up to the 14 inches. They fit snug in the frame, and I appreciated that. My boys love them and sleep in their beds with smiles. I will definitely purchase again when we need a mattress. Great price. The memory foam and support is nice, soft but still offers nice support. My kids tend to sleep warm and they were comfortable with the heat level so that was another plus. Nice material, I really like the black rather than the traditional white. Nicely made / sewn. No complaints here. I will upload pictures to add to this in case it's helpful to you.

### ⭐⭐⭐⭐⭐ Comfy, tall, good quality
*by T***N on August 28, 2025*

This arrived earlier than expected. It's quite comfortable and bouncy. I only gave it about 60 hours to fluff up though, didn't really have a funky smell other than "new carpet/fabric". I hit it with some smelly good spray just because though. It did reach the full 14inches but my 14in pocket sheets didn't quite fit. That could be a sheet problem though. It fit a twin frame perfectly and was fun to watch decompress. Should have gotten a video :( You can feel the springs around the edges when putting the sheets on but not while sleeping. I don't have any back or hip pain and sleep on my side and back. It's actually more comfortable that the Purple mattress in the other bedroom. Great quality for a mattress in a box!

### ⭐⭐⭐⭐⭐ Great Bed!
*by B***E on January 2, 2025*

I bought this bed wondering what quality it would be. I usually buy beds that are over $500. Surprisingly this bed is as comfortable as my current expensive bed. It "inflated" very quickly, after 2 hours it had expanded to 13 inches. It is great quality, feels very comfortable, is soft and firm at the same time. It seems very durable - not too soft or thin. You do not feel the springs at all! I plan to buy 2 more! Great value for your money. Definitely recommend!

---

## Why Shop on Desertcart?

- 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016
- 🌍 **Shop Globally** — Access 737+ million products across 21 categories
- 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price
- 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members)
- 🔒 **Secure Payments** — Trusted payment options with buyer protection
- ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews

**Shop now:** [https://www.desertcart.jp/products/791890698-duchessz-12-twin-size-mattress-in-a-box-medium-firm](https://www.desertcart.jp/products/791890698-duchessz-12-twin-size-mattress-in-a-box-medium-firm)

---

*Product available on Desertcart Japan*
*Store origin: JP*
*Last updated: 2026-01-23*