InnerSpace High Density 6-inch Twin-size Foam Mattress

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MSRP: $385.00 $225.01 (58%) off
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    InnerSpace High Density 6-inch Twin-size Foam Mattress
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    Made in USA

    Say goodbye to sleepless nights with this comfortable high-density foam mattress. Made with a thick foam core covered in a stretchy cotton, the mattress is designed to support your body evenly, reducing the pressure that leads to sore muscles.


    ITEM#: 14009790

    This resilient, high-density polyurethane foam core mattress distributes body weight evenly and eliminates uncomfortable pressure points. This mattress comes with a quilted cotton stretch knit cover.

    You can kiss those sleepless nights goodbye with this high-density mattress that supports every part of your body to reduce pressure that causes sore muscles and keeps you from sleeping well. The mattress is made of high-density poly foam with plush quilting on both sides. The mattress has a stretch knit quilted cotton cover.

    • Mattress measures 6 inches thick
    • Materials: High-density poly foam
    • Cover is quilted cotton stretch knit
    • Dimensions: 6 inches high x 38 inches wide x 75 inches long
    • Designed to fit all standard size twin beds with or without a box spring
    • Plush quilting on top and bottom
    • Spot clean mattress as needed
    • Mattress can be flipped if desired

    • Foam Tips:
    • Remove from packaging within 72 hours of receipt to maximize expansion.
    • This product arrives very tightly packed. Unwrap and allow 48 hours for this product to return to its original shape.
    • Being sealed in plastic packaging sometimes traps odors. After unwrapping, allow product to air for a few hours.
    • Due to machine-cutting manufacturing processes, there may be slight variances in the dimensions of this product.

    Firmness level of every item is unique. Please be advised that even similar products may produce different firmness results.

    Once opened this product is non-returnable.


    Mattress Type Foam
    Thickness 6 Inch
    Memory Foam Type Foam
    Support Medium
    Mattress Top Specialty
    Product Features Made in USA
    Recommended Foundation Type Bed Slats Box Spring Platform
    Dimensions See description
    Manufacturer Warranty 10 year Manufacturer
    Materials See description
    Model Number OSK-SLT-3875

    Customer Reviews

    5 Stars
    4 Stars
    3 Stars
    2 Stars
    1 Stars
    • Mom of 1

      Better than expected for the price. We purchased this for our daughter's daybed trundle. After unrolling it, we placed it right into the trundle and watched it reach its full size within a couple days. She loves it!

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    • foam mattress

      disappointed with the quality. shouldn't be show as 'HIGH DENSITY'. Didn't want to go thru the hassel of returning it. Still don't believe it is 6 inches after the 48 hour window. Wouldn't reccomend it!!!

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    • Very comfortable

      I bought these for the daybed in our guest room. But during my pregnancy I couldn't sleep on our bed, so I brought these from the guest bedroom and put them on the floor in our master bedroom and slept on them until I had my baby. They were soooooo comfortable, I slept like a baby. Unlike many pregnant woman, I was one that had a good sleep till the end!

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    • teen's room

      My teen loves this mattress, great quality and very comfortable!

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    • good deal

      had these for a while and they have held up well. Good deal

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    • Best purchase in a long time

      This is wonderful, we bought this for my dad becaue he has joint and back problems. The first night he slept on it he slept 9 hours straight through !!! this hasn't happened in years. So glad we bought it and at this price it is a steal !!!

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    • Buyer Beware!

      This bed is advertized as a 6" high density foam mattress but is only 4" thick with a nice padded cover that might add another 1/2 to 3/4". The foam itself is nice, but I need 6". I bought the twin size for my small travel trailer bed. After receipt of the first mattress, which expanded as advertised, I contacted Overstock, whose rep was very easy to work with. The first mattress was donated to a local women's shelter and they sent me another. It expanded to the same thickness, 4" from side seam to side seam. They offered me a 20% refund to keep the 4" one which I did. I have a 3" memory foam pad to put on top. Not ideal as the memory foam is softer than I like but will work in my trailer bed for now. As others have said, this mattress is OK for kids and bunk beds, but not really enough for a full size adult. Kudo's to Overstock for working to make it right.

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    • Great mattress

      This is a great mattress for the price. The only problem I had was being able to tell which side had the wool-blend for winter and which one had the cotton-blend for summer. It would be nice if there was a tag on it to distinguish which side was which. Otherwise, very satisfied!

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    • Comfortable

      Pleasantly surprised as far as the comfort of this mattress. Neither too hard nor too soft. But, contrary to the description, it did not expand to 6", thought. Barely 5". After letting it expand for several days now, I don't think it'll get any thicker, which is misleading. I had found this mattress at another site where they had several options, 4", 5" and 6", and in comparing prices, I figured the 6" model sold by overstock was the same price as the 5" (including shipping) from that other site. I wanted to make sure it was thick enough so that I would not feel the metal base underneath it. I don't, s o I am ok with that but I feel that Overstock should adjust its description. I would probably buy again this same product!

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    • Foam is the only way to go!

      This is our second time buying Innerspace mattresses. The twin is a little softer than I expected but plenty of support for my son. My husband and I sleep on a queen that is 8 years old and starting to get a little soft. We have converted 2 family members and 2 friends to Innerspace mattresses after sleeping on our bed. The comfort and price cannot be beat!

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    Questions & Answers

    Get your product questions answered right here.
    • Why did you choose this product?

      • Customer reviews and price

      • Needed new mattress for a guest twin bed. After reading reviews, decided to take a chance on this one.

      • Because of customer reviews being good.

      • just made sense to get all the pieces at the same time

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    • What does the 10 year warranty cover, and where is the warranty specified?

      • Hello skuffy, thank you for your inquiry. Unfortunately, the information you have requested is currently unavailable. We will continue to try and answer this for you. You will receive an email notification once an answer is posted. Have a great day.

    • Is this mattress CertiPUR-US certified?

      • Hello jg36, this mattress is not CertiPUR certified.Thank you for shopping with us.

    • Would this mattress work for bunk beds?

      • Yes that is exactly what we use it for. It is great and fits perfectly . Very comfortable ( a little soft for me) perfect for the kids : )

      • Yes, these are great for bunk beds. It also makes it easy to make the top bunk bed because they are light enough to lift up and tuck sheets in.

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    • What is the color? It looks beige but I'm guessing its white?

      • Hello brittnjule, This looks beige or off white when looking at the pillows. Thank you for shopping Have a great day!

      • is light beige

      • It's a cream and beige brocade pattern. Very classy looking in the neutral tones.

      • Mine arrived yesterday. It is beige, not white, and its slip cover has a more "traditional" quilted mattress look to it than some other foam mattresses I have seen. It looks pretty nice.

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    • how does it come packaged?

      • like size wise how big?

      • Hello nicolemaria, The InnerSpace High Density 6-inch Twin-size Foam Mattress arrives compressed, and very tightly packed. we recommend allowing the mattress to expand for 48 hours after opening. The dimensions of the shipping box are 41 inches high x 13 inches wide x 12 inches deep. Thank you for shopping with us.

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    • what kind of chemicals has this mattress been treated with?

      • Thank you for shopping with us hdmommy. The mattress is made from soy and the cover is cotton. I hope that helps.

    • If the mattress is not taken out of the wrapping, can it be returned if it feels too firm? If so, do I pay the shipping charges back or would I get a return label? Thanks.

      • Thank you for your interest in the InnerSpace High Density 6-inch Twin-size Foam Mattress. If the mattress received is damaged, the wrong size or any other defect then we will pay for it to be returned, but, if you receive it and you just don't like the firmness or the color or anything else then it is considered buyers remorse and even if it is unwrapped or unused you will still pay for the return shipping charges. If it is unwrapped or used then you may be able to return it, it would just have to be inspected by the warehouse for problems and then they would decide how much to give you back. It can be anywhere from 10% to 100% depending on the condition and circumstances. We hope this helps out. Have a great day.

    • Is the foam latex rubber or polyurethane foam?

      • Uncover the secret to continuous comfort. Our sleep luxury mattress is 6-Inch of durable, high-density polyurethane foam that conforms to your body and doesn't lose its shape. Additionally, when your spouse gets into bed, you won't roll off or bounce around, because the mattress has independent support and contains no springs. The plushly quilted, stretch knit cover add extra softness and durability. Thank you for your question. Please feel free to contact us again with any further questions.

    • Can this item be used with the durabed steel twin size platform with out a box spring? Also is it the right fit?

      • Yes. My son's bed is a platform bed with slats underneath the mattress and you do not feel the slats and the mattress does not appear to sink into the slats.

    • How is this mattress treated for meeting fire safety regulations? What chemicals are used? I saw a review mentioned cotton and wool, are these materials in the mattress?

      • The cover is a quilted cotton stretch knit cover and we use a fiber barrier under the ticking to obtain flame resistant properties. The fiber barrier is primarily Rayon, and there shouldn’t be any chemicals in the fiber. It is embedded with silica to achieve its flame resistant properties. Thank you for your question.

    • Hi, would this mattress be safe for my 2yr old son who is moving to a bunk bed? Is it too soft?

      • Being sealed in plastic packaging sometimes traps odors. After unwrapping, allow product to air for a few hours. This unit is not made of anything that can hurt or be harmful to the child. The question about being too soft really depends on the person the and their preference.

    • How long does it take for the mattress to fully decompress? I opened this to air out 3 days ago and it is still only 5"

      • It really should have fully expanded by now. Usually 72 hours is about what it takes to do that, but I would give it another day or so, since you are so close to that 72-hour mark. If it does not finish expanding after 4 days, it may be defective, and you will need to contact Customer Service at 1 800 843 2446 to make arrangements for a replacement.

      • It needs to air out for 48 hours.

      Read more Read less
    • Can you please find out what is the density in Ibs for this mattress? Thank you.

    • What is the weight of this mattress?

      • The shipping weight is 20 pounds, which is very close to the actual weight.

    • Will this work as a sofa sleeper mattress?

    • What is the recommended weight for this product

    • What is the exact density? 3lb? 4lb? 5.3lb?

    • how firm this mattress is?

      • Out of the 24 reviews on our site 2 people report it as being firm and many others state how comfortable it is. Another site that had less reviews but sold the same product reported this as firm but again comfortable. More of the other site reviewers used firm in their description.

    Shopping Guides

    Shipping & Returns


    Usually leaves our warehouse in 1 business day. *

    Mattress Return Policy:

    Mattress Sets are non-returnable upon signature at delivery. Mattresses are non-returnable if opened or taken out of their plastic wrapping.
    More Details

    Shipping Information:

    Our standard shipping method is ground shipping. We also offer expedited shipping for most items. Your final shipping cost and estimated delivery timeframe will be available at checkout.
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    ** Most Oversize orders are delivered within 1-4 weeks. Some orders may take 6 weeks to be delivered.