Sinomax Sleep 3-inch Gel Memory Foam Mattress Topper

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ITEM# 17340627
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      Included Warranty: 1 year Limited Manufacturer
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    ITEM#: 17340627

    Cushion your mattress and create a relaxing haven with a cozy Sinomax sleep gel memory foam mattress topper. The topper features an ample layer of dense gel-infused foam designed to mold to a persons form, relieving surface pressure, motion transfer between sleepers and reducing the need to toss and turn.

    The temperature sensitive technology allows the memory foam to adjust to body temperature and increase air flow, creating a warm and comfortable sleeping surface. The foam's naturally antimicrobial feature is ideal for people with allergies to ensure a clean sleeping experience, free from dust mites and other harmful bacteria.

    • A twin size mattress topper measures 4"H x 39"W x 75"L
    • A full size mattress topper measures 4"H x 54"W x 75"L
    • A queen size mattress topper measures 4"H x 60"W x 80"L
    • A king size mattress topper measures 4"H x 76"W x 80"L
    • Antimicrobial surface is resistant to dust mites
    • The surface of the foam is quilted and breathable for maximum comfort
    • The foam features a temperature sensitive technology to improve air flow

    • Twin: 4 inches high x 39 inches wide x 75 inches long
    • Full: 4 inches high x 54 inches wide x 75 inches long
    • Queen: 4 inches high x 60 inches wide x 80 inches long
    • King: 4 inches high x 76 inches wide x 80 inches long

    Memory Foam Tips:
    • Remove from packaging within 72 hours of receipt to maximize memory foam 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.

    Due to the nature of Memory Foam the firmness level of every item is unique. Please be advised that even similar products may produce different firmness results.


    Type Flat Topper, Mattress Topper
    Thickness 3 Inch
    Memory Foam Type Gel Memory Foam, Memory Foam
    Density 3 Pound
    Firmness Medium
    Dimensions See Details
    Warranty 1 year Limited Manufacturer
    Model Number 0671-SMX-TPR
    Country of Origin China
    • Verified Purchase
      Option: King

      Comfortable. Good quality and price.

      Read More
    • Very thick and plush!
      Verified Purchase
      Option: King

      Changed my night for the better! Current mattress is on the older side, and I was waking up at night with painful hips and shoulders (or maybe I'm on the older side, haha) - but adding this 3" topper saved me from buying an expensive new mattress. You do sink in quite a bit, so some may find the 2-inch thick enough. I would definitely choose this Gel Memory Foam over standard memory foam. Have had for 7 months and no wear and tear issues.

      Read More
    • Sinomax Sleep 3-inch Gel Memory Foam Mattress Topp
      Verified Purchase
      Option: Twin

      Definetly my best purchase in 20 years!

      Read More
    • Get the right size!
      Verified Purchase
      Option: King

      I bought this topper in King size because every Queen size I've bought has been several inches too small. So I got this oversized and cut the excess off. Now I have a perfect size topper. It is so comfortable under the mattress pad.

      Read More
    • Sleeping Again!
      Verified Purchase
      Option: King

      So comfy! I haven't slept this well for two years. Would highly recommend for anyone trying to improve and or extend the life of your mattress.

      Read More
    • Great Night's Sleep
      Verified Purchase
      Option: Queen

      I am delighted with this mattress topper! It turned my ancient 4" foam futon into a luxurious, comfy bed that lets me wake up with no sore hips, shoulders, or back. It is amply sized and cover the mattress completely. It has a quilted mattress pad with straps that keep it aligned on the mattress. There was no chemical odor. I'm very happy with this purchase.

      Read More
    • awful
      Verified Purchase
      Option: Queen

      Very hot to sleep in. Too soft and difficult to get out of. Can't stand it and don't recommend it. Expensive.

      Read More
    • perfect after my cropping

      I bought this mattress in King size for my Queen size bed. I have purchased a couple of foam toppers before (not this brand) and they were both undersized for the bed, being at least 4 inches too small on each side of the bed. So, I decided to buy large, and cut off the excess. The fabric cover is still King size, I just tuck it under, and now I have the perfect size mattress topper, AND enough left over for my dog's bed! The topper is very comfortable, you just sink into it. I like the 3 inch depth better than the 2 inch that I had before.

      Read More
    • Did the trick
      Verified Purchase
      Option: Queen

      Bought a medium memory foam bed that was a little too firm for comfort. This 3-inch gel foam mattress topper made sleeping a lot more comfortable. The thickness was just right. No more body soreness.

      Read More
    • 3" king size gel mattress topper
      Verified Purchase
      Option: King

      We purchased this item to improve our sleep. We are happy with the results. The size is a little bit too wide, so I'm not sure if it will stretch as time goes by. I would recommend this item and it was a good value.

      Read More

    Questions & Answers

    • Q:

      "Why did you choose this product?"

      • A:

        I have them on all my beds except one in the guest room of our vacation home. Now I do.

      • A:

        I needed a good quality memory foam. Will be returning if not expected quality.

      • A:

        It matched my specifications, had great reviews and was priced right. I look forward to receiving it and getting a better night's sleep.

      Read more Read less
    • Q:

      "Unwrapped my mattress topper and let air out/ expand yesterday in the afternoon. This morning the room smells chemical like. Current owners...does the smell ever go away???"

      • A:

        Hello Mermaid. For assistance with this issue please contact Customer Care at the number below. I hope this helps, thank you for shopping with us! U.S. and Canada Toll free: 1-800-The-BIG-O (843-2446).

    • Q:

      "We just ordered this, so I'm looking forward to writing a review in the near future. However, after the fact, I do have one question which might help others. This is listed as a 3" topper, but in the description, the dimension is 4" high. Can you verify one or the other (it might make a difference for the sheet pocket depth)."

      • A:

        It is a 3-inch mattress topper. Seems to be a typo in the product details.

      • A:

        Hello iowachoirmom, we do apologize for the confusion, this item is approximately four inches high. Thank you for shopping with us.

      Read more Read less
    • Q:

      "Does this topper have an odor?"

      • A:

        Hello cindinfocus, the topper should not have an odor. However, it has been stored in a warehouse so we recommend airing out the topper for 24 hours prior to use. It is also recommended to let the topper air out for 24 hours so it can expand to its natural shape. I hope this info helps. Thanks for shopping with us!

    • Q:

      "Is the cover removable?"

      • A:

        Hello iowachoirmom, no, this cover is not removable. Thank you for shopping with us!

    • Q:

      "is the Sinomax Sleep 3-inch Gel Memory Foam Mattress Topper made of gel foam or memory foam? I do not any flamable polyurethane. thanks"

      • A:

        Hello dcb, this is comprised of polyurethane gel and memory foam. Thanks for shopping with us!

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    Usually leaves our warehouse in 1-2 business days. *

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    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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    Items must be returned in new or unused condition and contain all original materials included with the shipment. For the return policy on a Marketplace item, please refer to the Seller’s individual policy, located on the product page by clicking on the Seller name. More Details

    FINAL SALE EXCLUSION: Items marked as FINAL SALE are not returnable unless the problem you experience is the result of our error.

    For your protection, all orders are screened for security purposes. If your order is selected for review, our Loss Prevention Team may contact you by phone or email. There may be a two business day delay to process your order.

    ** Most Oversize orders are delivered within 1-4 weeks. Some orders may take 6 weeks to be delivered.