AS4 View all Mattresses
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This mattress feels: Medium Soft Learn more

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The AS4 is our medium-soft mattress. It’s great for side sleepers, and anyone who likes more cushioning while they’re in bed. We combine our proprietary, cooling Bio-Pur™ foam and Affinity with SMT comfort foam layers to create a soft but responsive feel that relieves pressure points and makes you feel like you’re floating. Plus the high-performance Celliant® cover is made with thermoreactive yarn to safely turn body heat into infrared. Your comfort is guaranteed.

This mattress feels


Perfect for

Side Sleeper
Combo Sleeper


  • High-Performance Celliant® Cover
  • Hypoallergenic and dust mite resistance
  • No flip, no turn design
  • Maintains consistent pressure relieving support
  • Compatible with an adjustable bed foundation

What we're made of

  • Celliant® infused cover

    Celliant® infused covers improve blood flow while you sleep to help you fall asleep and stay asleep.

  • Green Guard fire sock
  • 4" Bio-Pur+ memory foam (4.0 lb density / 11 ILD)
    Amerisleep Bio-Pur+ Memory Foam

    Bio-Pur+ is an extreme open-cell memory foam that has gone through an additional process to allow for even more air to flow through the foam to keep even cooler throughout the night.

  • 1” Affinity layer with Surface Modified Technology (1.65 lb density / 23 ILD)
    Amerisleep Afinity LAyer

    Foam with Surface Modified Technology has built in channels to allow air to circulate through the mattress more freely so you won’t heat up at night. These also redistribute pressure points and alleviate pain.

  • 7" Bio-Core support layer (1.5 lb density / 35 ILD)

Quality assured

  • SFC Approved
    SFC Approved

    The Sustainable Furnishings Council is a non-profit balanced coalition of industry players founded to promote products designed to support environmental stewardship.

  • Made in the USA
We've got it all covered
And put just as much thought into what's inside.
Your mattress will be wrapped in a Celliant-infused cover. Celliant® is a thermo-reactive thread that has been clinically proven to help people fall asleep 15 minutes faster on average. It does this by using your natural body heat and recycling it into infrared light. This healing energy will help you wake up with more energy and less aches and pains.
Our new, extreme open-cell memory foam provides maximum breathability and pressure relief. By taking our Bio-Pur™ foam through an additional process, we make it 70% more breathable. Sleeping on Bio-Pur+™ is great for those looking to sleep as cool as possible.
Affinity layers transition between the other layers in the mattress to amplify their supportiveness and responsiveness. Your bed will feel softer while still supporting thanks to this layer. With Surface Modification Technology, precise channels are carved into this layer so more heat and moisture can flow away from your body. SMT also provides additional pressure relief for your pain points.
The Bio-Core™ base layer provides solid support designed to preserve natural alignment without contributing to pressure points. Amerisleep's Bio-Core™ is composed of high-density material for comfort that lasts.
Sleep that's got your back.
And side. And stomach.

Buying a mattress online can seem risky, but with our guarantees you can put fear to bed. While we strive to match customers with the best mattress the first time, trying a mattress in your own home is the true test of comfort. If you are not satisfied with your mattress, ship it back to us within 100 days for a full refund.

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