Twin XL Serta iComfort CF4000 Firm Mattress

Twin XL Serta iComfort CF4000 Firm Mattress

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$84.77/mo suggested payments with 48 months special financing.
$82.47/mo suggested payments with 36 months special financing.
$61.08/mo suggested payments with 36 months special financing.
$79.42/mo suggested payments with 36 months special financing.
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Twin XL Serta iComfort CF4000 Firm Mattress
Twin XL Serta iComfort CF4000 Firm Mattress

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Comfort This describes how a mattress feels. The Comfort Scale rating is based on how the cushioning materials conform to the body's shape. The higher the number the softer the mattress.

Quilt - Top of Mattress This is the outside cover on the top of the mattress. It covers and protects the comfort and support layers inside.

Comfort - Padding Layers This provides a cushioning layer between you and the support system in the bed. Different kinds of padding will provide different levels of comfort.

Correct Back Support System This is a general term used to describe how a mattress distributes and stabilizes body weight and maintains proper spinal alignment. Different materials provide different levels of support.

  • 7" Serta Foam Core

Box Spring - Foundation (optional)

Warranty This tells you what kind of warranty you have and how long it will last. A typical warranty lasts about 10 years.

Made In This tells you where your mattress is manufactured.

  • United States


  • MATT-929261, STD-929407 ,LP-929401, FRAME-928795

Expert Review

Expert Review video placeholder

My Take On The Serta iComfort CF4000 Firm Mattress

by Jed Harrington

If you're looking for a luxurious, top of the line feel, with some of the most advanced comfort materials in the mattress industry, you've found it, with the Serta iComfort CF4000 Firm. This mattress has everything you need to start enjoying supportive, restful sleep, well into the next decade.

True Neutral Comfort

The CF4000 Firm isn't exceptionally firm or soft, which makes it a fantastic all around choice. Firm enough for back sleepers, yet soft enough for most side sleepers, this mattress is designed to please a wide range of body types and sleeping positions.

Exceptionally Cool

Sleeping cooler promotes falling asleep faster, and makes your mattress more comfortable than one that feels warm. This is where the CF4000 shines. The Max Cool Cover and UltraCold System combine to provide a cool to the touch comfort that works so well, you can feel it even through jeans.

Air Support Foam

The CF4000 models are the only models to feature the newly developed Air Support Foam. Exclusive to Serta, this comfort material moves with your body and smartly contours to your unique shape to help alleviate aches and pains.

Solid Support

The solid foam core feels very supportive while providing a high degree of body contouring. Unlike coil systems, this support system eliminates virtually all motion for undisturbed sleep and is 100 percent compatible with all adjustable bases.

CertiPUR US Certified

Sleep with peace of mind, knowing all the comfort materials have been independently tested by CertiPUR-US to meet or exceed the highest quality standards.

One Of The Finest Top Of The Line Models

I loved the CF4000 Firm. This mattress has a very high end, substantial feel that is simultanously soft and firm. The cooling feature is incredible and the Air Support foam adds a layer of luxury unlike other mattresses in this category. Overall, Serta did a great job on this model and for the money, offers a great deal more than their competition.


Cal King13.5"72"84"
Twin XL13.5"38"80"

Works With All Bed Types

Box Spring
Box Spring
Traditional Frames
Traditional Frames
Adjustable Bases
Adjustable Bases

Your mattress purchase is fully compatible with all modern support systems, including adjustable base, platform bed, box spring/foundation, even the floor!

Customer Reviews

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  • Sleep cooler through the night with DualCool Technology
  • Feel supported with 900 Series Pocketed Coils
  • Consistent comfort with the BeautyEdge Foam Encased Edge