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Plank Firm Luxe Hybrid Mattress (With Cooling Cover)

Plank Firm Luxe Hybrid Mattress (With Cooling Cover)

4.5
120 Reviews
Best Seller

Sleep firm. Flip often. The Plank Firm Luxe Hybrid Mattress by 3Z is a bold take on ultra-firm comfort, and it’s flippable for two levels of firm feel. Designed for back sleepers, stomach sleepers, and firm mattress lovers, this bed features a hybrid construction of high-density foam and individually encased coils for maximum stability and minimal motion transfer.

Each mattress comes equipped with the GlacioTex™ cooling cover for advanced temperature regulation, offering a cool, breathable sleep surface that supports firm comfort.

PLEASE NOTE: TWIN SIZE DOES NOT INCLUDE THE GLACIOTEX™ COOLING COVER. ALL OTHER SIZES COME WITH GLACIOTEX™ BUILT IN.

Why You'll Love It:

  • ✅ 2-Sided Ultra-Firm Design (Firm + Firmer sides)

  • ✅ Hybrid: Dense foam + individually wrapped coils

  • ✅ Reinforced edge support for full-surface comfort

  • ✅ GlacioTex™ Cooling Cover (except Twin)

  • ✅ Ideal for sleepers with back pain or needing orthopedic-style firmness

Available Sizes: Twin, Twin XL, Full, Queen, Olympic Queen, King, California King

Made by 3Z Brands | Shop Exclusively at SleepCity

$898.50
$1,198.00
Save $299.50
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Client Ratings & Reviews
Trusted by Thousands—See Our Top-Rated Reviews
Amazing purchase!
Absolutely thrilled with my new mattress! The quality is truly top-notch.
John A.
Amazing purchase!
Absolutely thrilled with my new mattress! The quality is truly top-notch.
John A.
Amazing purchase!
Absolutely thrilled with my new mattress! The quality is truly top-notch.
John A.
Amazing purchase!
Absolutely thrilled with my new mattress! The quality is truly top-notch.
John A.
Amazing purchase!
Absolutely thrilled with my new mattress! The quality is truly top-notch.
John A.
Amazing purchase!
Absolutely thrilled with my new mattress! The quality is truly top-notch.
John A.
Amazing purchase!
Absolutely thrilled with my new mattress! The quality is truly top-notch.
John A.
Amazing purchase!
Absolutely thrilled with my new mattress! The quality is truly top-notch.
John A.
Amazing purchase!
Absolutely thrilled with my new mattress! The quality is truly top-notch.
John A.
Amazing purchase!
Absolutely thrilled with my new mattress! The quality is truly top-notch.
John A.
Amazing purchase!
Absolutely thrilled with my new mattress! The quality is truly top-notch.
John A.
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Frequently Asked Questions
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The best mattress for your sleeping position depends on your body type and comfort preferences. For side sleepers, a medium-soft to medium mattress is ideal to provide pressure relief at the shoulders and hips. Back sleepers typically need a medium-firm mattress that offers support for the spine, while stomach sleepers may prefer a firmer mattress to avoid lower back strain. If you’re unsure, our mattress quiz can help you find the perfect fit!

The best mattress depends on your sleeping position and body type.

The best mattress depends on your sleeping position and body type.

The best mattress depends on your sleeping position and body type.

The best mattress depends on your sleeping position and body type.

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