Serta Perfect Sleeper X Quilted Hybrid Knox Firm 13.5 Inch Mattress on a modern wood bed frame.
Serta Perfect Sleeper X Quilted Hybrid Knox Firm 13.5 Inch Mattress on a modern wood bed frame.
Perspective view of Serta Knox Firm 13.5 Inch Quilted Hybrid Mattress with a decorative floral cover.
Perspective view of Serta Knox Firm 13.5 Inch Quilted Hybrid Mattress with a decorative floral cover.
Front view of Serta Perfect Sleeper X Knox Firm mattress featuring cooling and 5-zone support labels.
Front view of Serta Perfect Sleeper X Knox Firm mattress featuring cooling and 5-zone support labels.
Top view of the breathable floral quilted cover on the Serta Perfect Sleeper X Knox Firm mattress.
Top view of the breathable floral quilted cover on the Serta Perfect Sleeper X Knox Firm mattress.
Profile of the 13.5 inch Serta Knox Firm mattress featuring a durable dark grey quilted border.
Profile of the 13.5 inch Serta Knox Firm mattress featuring a durable dark grey quilted border.
Close-up of Serta Perfect Sleeper X branding on the Knox Firm 13.5 inch hybrid mattress corner.
Close-up of Serta Perfect Sleeper X branding on the Knox Firm 13.5 inch hybrid mattress corner.
Knox Firm mattress diagram showing 5 ZoneActive support, cooling tech, and hybrid comfort layers.
Knox Firm mattress diagram showing 5 ZoneActive support, cooling tech, and hybrid comfort layers.
Serta Knox Firm mattress comfort scale showing firm support ideal for back and stomach sleepers.
Serta Knox Firm mattress comfort scale showing firm support ideal for back and stomach sleepers.
Serta mattress layers diagram showing firm zoned support and advanced cooling technology.
Serta mattress layers diagram showing firm zoned support and advanced cooling technology.
Serta Perfect Sleeper X Quilted Hybrid Knox Firm 13.5 Inch Mattress

Brand Serta

$899.00
$1,499.00
Save $600.00
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Best For

Back & Side Sleepers

Firmness

Firm Comfort
Only 17 left in stock
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Only 17 left in stock

Free Delivery to your  House in 1-2 Weeks.

Free USA Wide Delivery

We offer free delivery on orders over $100. Ships within 1–2 weeks 

Mattress Size

✅ Twin: Provides a comfortable sleep space for one child or adult.

✅ Dimensions: 38" wide x 74.5" long.

 

✅ Full: Children, Single Adults, Adults with Children and/or Pets.

✅ Dimensions: 53" wide x 74.5" long.

 

✅ Queen: The most popular size, providing ample space for two adults to sleep comfortably.

✅ Dimensions: 60" wide x 79.5" long.

 

✅ King: Experience generous space without crowding your partner.

✅ Dimensions: 76" wide x 79.5" long.

 

✅ California King: Perfect for taller individuals, ensuring a comfortable sleep.

✅ Dimensions: 72" wide x 83.5" long.

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key mattress benefits
Firm Zoned Support for Proper Alignment

Engineered with 5 support zones to provide targeted support across your body—ideal for back and stomach sleepers.
Hybrid Pressure Relief System

Combines responsive coils with Perfect Conform™ Graphite Memory Foam to cradle pressure points while maintaining firm support.
Reduced Motion Transfer

Designed to minimize movement across the mattress, helping couples enjoy more restful, uninterrupted sleep.
Advanced Cooling Technology

Graphite-infused memory foam and Cool Twist® Gel Foam help redistribute heat for a cooler, more comfortable sleep.

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Address - 6075 Old Canton Rd, Jackson Ms 39211

Phone Number - 800-540-9851

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Serta Perfect Sleeper X Quilted Hybrid Knox Firm 13.5 Inch Mattress on a modern wood bed frame.
Perspective view of Serta Knox Firm 13.5 Inch Quilted Hybrid Mattress with a decorative floral cover.
Front view of Serta Perfect Sleeper X Knox Firm mattress featuring cooling and 5-zone support labels.
Top view of the breathable floral quilted cover on the Serta Perfect Sleeper X Knox Firm mattress.
Profile of the 13.5 inch Serta Knox Firm mattress featuring a durable dark grey quilted border.
Close-up of Serta Perfect Sleeper X branding on the Knox Firm 13.5 inch hybrid mattress corner.
Knox Firm mattress diagram showing 5 ZoneActive support, cooling tech, and hybrid comfort layers.
Serta Knox Firm mattress comfort scale showing firm support ideal for back and stomach sleepers.
Serta mattress layers diagram showing firm zoned support and advanced cooling technology.

Serta Perfect Sleeper X Quilted Hybrid Knox Firm 13.5 Inch Mattress

$899.00