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SINWEEK

SINWEEK 4 Inch Gel Memory Foam Mattress Topper, King Size

  • Based on 621 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon
Arrives Friday, Oct 9
Order within 18 hours and 37 minutes
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Size: King


Style: 4 Inch


Features

  • GEL MEMORY FOAM MATERIAL: Our memory foam mattress topper readily conforms to the curves and shape of your body, distributes weight evenly to alleviate pressure points for better sleep.
  • MORE COMFORTABLE SLEEP: The cooling gel mattress topper reduces heat and improves airflow, keeping you dry and comfortable all night. Customize your sleep experience for the perfect balance of softness and support.
  • SOFT BUT NOT FOLDABLE: Our mattress topper is soft and comfortable, but do not roll it up for long-term storage after opening, and avoid placing heavy items on top to prevent tearing.
  • CertiPUR-US CERTIFIED: Our Gel Swirl memory foam topper is made of CertiPUR-US certified materials. The Gel Swirl memory foam topper meets or exceeds standards for content, emissions, and durability.
  • BEFORE FIRST USE: Leave the memory foam flatly in a well ventilated area for 48-72 hours until its fully expanded. In addition, we offer a three-year warranty and 24-hour manual customer service to ensure your after-sales service.
  • IMPORTANT: This product is intended to be used on top of an existing mattress and is not designed for standalone use.

Description

The mattress topper has holes for ventilation to promote air circulation and enhance refreshing comfort, increaseing airflow and breathability to help regulate body temperature while you sleep. This mattress topper is made from dense gel memory foam that snugly fits around your body to relieve pressure and provide optimum support for comfortable deep sleep all night long. Wake up feeling refreshed and energetic all day. Certified by CertIPUR-US, ensure your uncompromising safety Topper is compressed, rolled, boxed, and shipped right to your front door. Leave the memory foam flatly in a well ventilated area for 48-72 hours until it’s fully expanded.

Brand: SINWEEK


Color: 4 Inch


Size: King


Special Feature: Temperature Control


Closure Type: Pull On


Brand Name: SINWEEK


Age Range Description: Adult


Model Name: Purple


Number of Items: 1


Manufacturer: SINWEEK


UPC: 754525795360


Item Highlight: Ventilated Soft Pressure Relieve Mattress Pad, Breathable Bed Topper, CertiPUR-US Certified, King Size


Unit Count: 1 Count


Number of Packs: 1


Model Number: MTDK-CA


Other Special Features of the Product: Temperature Control


Closure Type: Pull On


Water Resistance Level: Not Water Resistant


Item Firmness Description: Soft


Product Care Instructions: Dry Clean Only


Material Type: Memory Foam


Size: King


Color: 4 Inch


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Friday, Oct 9

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Similar Products

Top Amazon Reviews

    • Comfort and price, both EXCELLENT!
Color: 4 Inch Size: Twin
I LOVE THIS!!!! After 13 spinal surgeries, it's always been very very difficult to find comfort sleeping. I now feel like I'm floating! Also, my dogs keep stealing my spot!
Reviewed in the United States on March 1, 2026 by Amazon Customer
    • So comfortable, great value
Color: 4 Inch Size: Twin
I really like this twin sized mattress topper. When I first bought it, I was worried it was too small for my twin bed. However, after 24 hours, it fully expanded to the correct size. It turned my hard memory foam mattress into a soft cloud, and I really love it. I got the 4 inch kind, which I was hesitant about because I thought it might be too cushy, however, I’m very happy with it. It did take a couple of days for the chemical smell to dissipate, but now it’s fine, and I absolutely love it. It makes sleeping on my side easier. I also bought a softer memory foam pillow to complement the softer mattress topper. Others in the reviews have mentioned that the topper can rip easily, and this is true— it is heavy but delicate, so when you lift it to place it on the bed, be careful not to let it tear. However, now that it is on the bed, it is fine. This was a great and relatively cheap investment. I have had the topper now for several weeks, and still love it. ... show more
Reviewed in the United States on October 11, 2023 by Alexandra Spark
    • Firmer than expected
Color: 4 Inch Size: Queen
Review Image by tlark tlark
*Update* customer service has reached out and was willing to fairly rectify the situation. Although the mattress topper did not fit my needs, their concern was to ensure that I was completely satisfied. I truly appreciate the prompt response, when reaching out regarding the product, and the follow up afterwards. Because of this I am changing my review rating, of my own volition. I feel it is only fair to review the product based on product quality and customer service. As stated before this mattress topper may have been perfect for someone else. However, it did not work for me. The product is still of excellent quality and customer service is great. It is my hope that the company continues to ensure great customer relation. ***Original review***This topper was not what I expected and I am truly disappointed. After carefully reading the listed product’s details and reviews, I decided to purchase this topper in hopes of achieving a better nights sleep from my current mattress. After sleeping on the topper, I have now experience body pain when waking up. According to the listing, this topper is advertised as on the softer side as to opposed to firm. Unfortunately, this is not the case. I have tried it for 2 nights and wake up with pain each time. It is very difficult to sleep on because of its firmness rendering it unusable. There is absolutely no way of returning it after expansion so be sure this is the one for you. It is true to size and a quality foam topper, just not what was expected based on listed information. Just be mindful that it is firm, so for those looking for a firm topper, this is defintely the one for you. If you are looking for a softer topper, continue to do more research. I have reached out to customer service for advisement, and I did get an immediate email back regarding my issue. It is my hope that a fair resolution can be reached. I am giving it a one star review due to the inaccuracies of the listing and the inconvenience it has caused. I will update my review regarding customer service quality soon.... ... show more
Reviewed in the United States on November 29, 2025 by tlark tlark
    • Thick and yes!!
Color: 4 Inch Size: Full
Perfect, thick and comfortable
Reviewed in the United States on February 19, 2026 by Bertinelli
    • So good, I’m having lucid dreams.
Color: 4 Inch Size: Twin
My back and my hips love this. I have a deep natural arc in my back and my hips are curvy so this covers everything a hard flat bed wouldn’t. If you end up on a bed with springs, this will make you forget they’re there. I’m in a temporary housing situation, so this is great to remove and roll up later, as the owner prefer rock hard beds. The rebound time of the material is fairly quick. As I slide in and out of consciousness in sleep and occasionally reposition. I can feel the foam, repositioning to fit my body. My sleep quality has improved so much I’m having lucid dreams. It’s easy to put on, just slide it under your fitted sheet. It’s worth every dime if you value sleep and need support and recovery after strenuous days. ... show more
Reviewed in the United States on January 18, 2026 by Bradlie
    • Don’t buy
Color: 4 Inch Size: Twin
Review Image by Tricia Tricia
Deformed and hard as a rock
Reviewed in the United States on December 6, 2025 by Tricia Tricia
    • Pricey but good quality
Color: 4 Inch Size: Twin XL
It's really pricey and super firm after you open it and let it take shape, it'll take a while to break it in.
Reviewed in the United States on February 8, 2026 by TheSpookyCatLady
    • A Good size, comfy....
Color: 4 Inch Size: Twin
It has a serious issue with slippage....I have to shoce it back against the wall every time I climb into it.
Reviewed in the United States on November 16, 2025 by Michael-Linn Beebe

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