King Memory Foam Mattress Topper Firm, 4 Inch Extra Firm Mattress Topper for Back Pain Relief, Copper Infused Cooling Bed Topper with Washable Cover & Non-Slip Base, CertiPUR-US Certified
Condition: New
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FREE 30-day refund/replacement
To qualify for a full refund, items must be returned in their original, unused condition. If an item is returned in a used, damaged, or materially different state, you may be granted a partial refund.
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Availability:
Only 5 left in stock, order soon!
Arrives
Thursday, Oct 9
Color: 4 Inch Light Grey
Size: King
Features
- 4-Inch Dual-Layer Design for Personalized Comfort: FANCYLION king mattress topper features a memory foam top layer that molds to your bodys curves, cradling your spine for optimal pressure relief, while the extra-firm support foam base reinforces proper spinal alignment, ensuring restful sleep all night.
- Copper-Infused Cooling Gel Memory Foam: Our innovative copper-infused memory foam topper actively draws heat away from your body, regulating temperature all night long, perfect for hot sleepers.
- Ideal for back pain relief and all sleepers: The memory foam mattress topper relieves back pain, supports every sleeping position (back, side, or stomach), provides specialized comfort for pregnancy, and revitalizes overly soft mattresses.
- Washable & Non-Slip Design: The removable, machine-washable cover makes cleanup effortless, while the non-slip bottom keeps your bed mattress topper securely in place all night.
- Elevate Your Sleep: Fancylion mattress topper delivers hotel-quality luxury, backed by a 90-night trial and 12-month warranty. Love it or return it hassle-free.
Brand: Fancylion
Color: 4 Inch Light Grey
Size: King
Fabric Type: Polyurethane
Special Feature: Memory Foam, Washable, Zipper Off
Brand: Fancylion
Color: 4 Inch Light Grey
Size: King
Fabric Type: Polyurethane
Special Feature: Memory Foam, Washable, Zipper Off
Closure Type: Zipper
Product Care Instructions: Machine Wash
Water Resistance Level: Not Water Resistant
Age Range (Description): All Age
Material: Memory Foam
Model Name: FB4K
Number of Items: 1
Manufacturer: Fancylion
UPC: 730763926179
Product Dimensions: 76 x 80 x 4 inches
Item Weight: 34.7 pounds
Item model number: FB4K
Date First Available: August 20, 2025
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Thursday, 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.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
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Similar Products
Top Amazon Reviews
Color: 4 Inch Light Grey
Size: King
This is a 5 star product! I read and re-read all the reviews and product description. That changed my mind to purchase the 4" as it's made of 33% denser foam. It was the right decision! Pkg was delivered 2 days early. Opened the box and slid product out. Instructions and tool to cut plastic were right on top. When you roll out the topper, turn it over so that the zipper is accessible. It'll be easier to zip it back up that way. Do open cover completely so the foam can expand for a full 24 hours. There was zero odor. I opened and left it on the floor in entryway. Once we got it situated on the bed, we plopped down on it and it was instantly comfortable. Supportive and soft at the same time. Would purchase again!
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Reviewed in the United States on September 18, 2025 by DEB IN FL
Color: 3 Inch Light Grey
Size: Queen
My gel/memoryfoam mattress has served me for a few years now. However, lately I got up with my back and hips hurting. I have had Rheumatoid Arthritis for 40 yrs and back problems. When I read the reviews by others I decided to give this topper a try. I have had it now laying on top of my mattress for about a week. I am getting up in the morning with almost no pain at all and sleep much better. Not sure about the cooling. Although the topper does feel cool to the touch I am not sure if it actually is sufficient to cool my body. The firmness and comfort is perfect for me.
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Reviewed in the United States on September 19, 2025 by MaggieA
Color: 3 Inch Light Grey
Size: Queen
This came shrink-wrapped (as most products like this do). I took it out and let it expand for 24 hours prior to use. Even after 24 hours, the pad never quite got up to the 3" mark, more like 2.75". There was no bad smell at all, even right out of the package, which I appreciated. The mattress pad has a cover with a non-slip base and loops to fit around your mattress to keep it from sliding around. The cover is allegedly washable, which is nice, although trying to get it off and back on would probably be a monumental task and I have a feeling it would never fit the same again. This thing is pretty pricy - almost as much as a whole cheap memory foam mattress, so I was not sure I'd think it was worth it... I've been sleeping on it now for a week and it is worth the cost. It has made my old, worn-down memory foam mattress feel new again. I sleep on my back and slept better from the first night. It is pretty soft so it would probably be good for side sleepers, too. I know others have said it kept them cool and that has not been my experience because I sink down into it a little more than I did with just my mattress, but it doesn't feel hotter than my mattress either, just about the same temp. I recommend it.
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Reviewed in the United States on September 12, 2025 by Triplet Reviews Triplet Reviews
Sleeping on this memory foam topper has been such a big upgrade for my bed. My twin mattress was on the firmer side, and after a couple of nights I’d usually wake up with some stiffness in my back. Adding this 3 inch topper gave me just the right amount of cushion without sinking in too deep. It feels supportive, especially around my lower back and shoulders, and I’ve noticed I’m waking up with less tension.The copper infused foam really does a decent job of keeping things cooler. Normally memory foam tends to trap heat, but this topper feels more breathable，I don’t wake up as hot in the middle of the night. The cover is soft and smooth, plus it zips off and washes easily, which makes keeping it fresh much simpler. The non-slip base is another thoughtful touch, because once I set it on the mattress it didn’t shift around at all, even when I tossed and turned.I’ve been using it for about two weeks now, and the difference in my sleep quality is noticeable. It still feels firm enough to support me, but with a nice contouring effect that relieves pressure points. For anyone dealing with back pain or just looking to soften up a stiff mattress, this topper is well worth it.
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Reviewed in the United States on September 7, 2025 by echo
My previous mattress was too soft, and after a while, I felt like my lower back wasn't supported, leading to frequent morning soreness. Since switching to this thicker mattress, I've felt much more comfortable. The dual-layer design is ingenious. The upper layer, made of soft memory foam, conforms to the body's curves, comfortably cradles the spine, shoulders, and neck. The lower layer is firmer, supporting the spine and keeping it in the correct position. The combination of these two layers provides both support and comfort, making it ideal for someone like me who is prone to lower back pain. The dual-layer design is particularly noteworthy. The firm lower layer keeps the spine in the correct position, while the soft upper layer provides a sense of security and comfort, allowing me to sleep soundly all night.
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Reviewed in the United States on September 26, 2025 by Will
This extra firm memory foam topper is exactly what I needed for better support. It’s 3 inches thick, which adds a strong layer of firmness to the mattress and helps relieve pressure on my back. Lying down feels more stable, and I wake up with less stiffness. The copper infusion is a nice touch, because it helps with cooling, and the bed doesn’t feel as warm as before. The cover is removable and washable, which makes maintenance easy, and the fabric feels soft and smooth against the sheets. I also like that the non-slip base actually works—it holds the topper in place without shifting. The overall design is simple but well thought out, and it fits securely on a twin bed. The foam feels supportive without sinking too much, which is perfect if you prefer a firmer surface. It combines support, cooling, and easy care in one topper.
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Reviewed in the United States on September 18, 2025 by Eva
This topper has a 2.5-inch thickness, which makes a noticeable difference in support. My back feels properly aligned when lying flat, and it doesn’t sink down after long use. The cover is soft, removable, and washable, and the non-slip base keeps it steady on the bed. The overall build feels solid and well-made. It also regulates heat better than my old foam pad, so nights feel cooler and more comfortable. The firmness works well for easing back pressure without being too hard. For the quality and durability at this price, it’s a great value and a good choice to improve your mattress.
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Reviewed in the United States on September 18, 2025 by Gorye