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SLEEPWELL® Mattress in a Box

Sleepwell MB300 $279.00$429.00

At the End of Your Day, Go Home to SLEEPWELL®


The MB300 is the crown jewel of our Mattress in a Box line. Each MB300 mattress is crafted with thicker Firm- and Gel-Foam layers and Visco-elastic “Memory Foam” to cradle your body through a good night’s sleep. The quality materials and craftsmanship are evident the first time you lie down on it. Not only will you immediately feel the cushioning and support that comes with a high-end mattress, but it’ll also feel that same way many years from now.

  • 6″ Firm Foam Core
  • 2″ Firm Foam layer
  • 2″ Plush Gel Foam Layer
  • 2″ Plush Visco-elastic “Memory Foam” layer
  • All covered by a Cooling Cover**
  • FireShield Encasement* Covering the Entire Mattress
  • Overall height: appx. 12″

We'll give you 100 nights to test out your new mattress.


Designed and Manufactured in the USA


We are proud to present our brand new Mattress in a Box product line. Designed and manufactured in our Maryland factory to our high standards for materials and craftsmanship, your mattress will provide you with many nights of wonderful, restful sleep.

And since you are buying directly from the manufacturer of a famous national mattress brand with its factory in Maryland, you pay less. Chances are you will notice our prices are 15% - 20% less than other online mattress retailers. That's because you pay only for the mattress - there are no additional overhead and marketing costs.

You have three options to choose from, based on what you are looking for and how much you want to spend. All are shippable, portable, and versatile to suit your lifestyle. And live up to Sleepwell's reputation for comfort and durability.

Convenient Shopping

Bed in a box mattresses are shipped right to your doorstep, taking the hassle out of mattress shopping. Plus, the ability to buy online frees up your weekend, and refunds are easy*

100-Night Risk-Free Trial

Test-driving a mattress is the secret to finding the perfect mattress. Try our mattress for 100 nights and decide if it provides the right sleep quality for you.


For over 85 years, Sleepwell has been providing retailers and their consumers with the best quality mattresses and bedding on the market.

Product Specs

Sizes: Twin, Full, Queen, King
Twin: 74×37.5×12
Full: 74.5x52x12
Queen: 79×59.5×12
King: 79×75.5×12

Weight: 63 lbs. (Weight is of a queen mattress; twin & full are less, king is more.)
Overall height: approx. 12”

FireShield Encasement* covering entire mattress
6″ Firm Foam Core plus 2″ Firm Foam layer
2” Visco-Elastic “Memory Foam” layer
2” 2.5 pound, Plush Gel Foam layer
Covered by a Cooling Cover**

*Meets US Flammability Regulations 1632 & 1633

**Cover treated with Phase-Change-Material to simulate “coolness”