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Sleep X | Firm

Sleep X | Firm

Ultra-Firm Support + Cooling

Gold collection

27+ people bought

  • Hand-Tufted Durability: A hallmark of luxury craftsmanship, hand-tufting secures every layer of the mattress together, preventing shifting and increasing the mattress's lifespan and long-term supportive feel.
  • Double Lumbar Support: This unique system provides two layers of targeted back support: a zoned, reinforced center on the coil unit and a dedicated lumbar band of copper-infused Talalay latex for unparalleled spinal alignment.
  • Cooling & Responsive Latex: Naturally breathable and buoyant Talalay latex offers instant pressure relief without the "sinking" feel of memory foam, while copper infusion enhances its cooling and antimicrobial properties.
Mattress height:
14"
Sleep type:
  • Stomach sleeping position
    Side sleeping position
    Back sleeping position

    All sides

  • Mattress type:

    Individual pocketed coil

    Comfort/Feel:

    Firm

    Size Size guide

    Queen

    $2,099.95

    $1,699.95

    King

    $2,599.95

    $2,099.95

    Bed frame options

    Total Price
    $1,699.95 $2,099.95 Save $400

    In stock. Delivery by September 05

    Our benefits

    100-Night Trial

    Free One-Day Delivery

    10 Year Warranty

    Learn more

    Materials

    Construction of Mattress:

    7 Layer Design, 14" Profile

    • Hand-Tufted Artscape Cooling Quilt with Gel-Infused & Firm Foams
    • 0.5” Copper-Infused Natural Talalay Latex Lumbar Support Band
    • .75” Layer of Copper Infused Natural Talalay Latex Foam
    • .75” Layer of Copper Infused Natural Talalay Latex Foam
    • 2” Layer of 2.0lb Density Support Foam
    • 13-Gauge 768 Extra Firm Pocketed Coil System with Reinforced Edge & Lumbar Support
    • 1” High-Density Base Foam
    • Shift-Resistant Lower Cover


    Basic Care: Spot clean with a mild detergent, such as upholstery cleaner. We highly recommend using a waterproof mattress protector to ensure the longevity of your mattress.

    Certifications

    All foams meet CertiPUR-US® standards for content, emissions, and durability, and are analyzed by independent, accredited testing laboratories.

    Protected by a chemical-free and fiberglass-free fire barrier meeting 16 CFR 1633 and 16 CFR 1632 compliance

    Warranty

    10-Year Warranty

    If defects in materials or workmanship arise, Sleeptronic will repair or replace your mattress for as long as you own it. Pair with Mattress King's 100-night risk-free trial for total peace of mind.

    View full warranty details here

    Where it’s made

    American Craftsmanship: Made in Texas

    Expert Assistance Awaits

    Get expert advice from our sleep specialists to ensure your best night’s sleep.


    OR


    Prefer a Personal Touch? Book Your In-Store Visit to discover mattresses and sleep essentials customized for your comfort.

    View full details

    The Apex of Handcrafted Support and Durability

    The Sleep X Firm is our strongest mattress, built without compromise. Traditional hand-tufting ensures lasting durability, while a unique double lumbar system and cooling copper Talalay latex provide incredible support and pressure relief. It's all built on a heavy-duty 13-gauge coil unit for a truly firm, restorative feel.

    layers
    firmness

    Firmness Scale

    1-3

    3-4

    4-6

    6-8

    8-9

    9-10

    Plush

    Medium-Plush

    Medium

    Medium-Firm

    Firm

    Extra-firm

    support

    Support

    Low

    Medium

    High

    circulation

    Pressure Relief

    Basic

    Average

    Advanced

    circulation

    Air Circulation

    Good

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    Best

    Customer Reviews

    Discover what our customers say about Mattress King.

    4.9

    2,148 reviews

    Frequently Asked Questions

    What is hand-tufting and why is it important in a mattress?

    Hand-tufting is a traditional, premium craftsmanship technique where twine is threaded through every layer of the mattress—from the top quilt to the bottom—and then secured on both sides. This meticulous process locks all the comfort and support layers firmly in place, preventing them from shifting, bunching, or sagging over time. It dramatically increases the mattress's durability and provides a more consistent, supportive feel for its entire lifespan.

    How does the "double lumbar support" system work?

    The Sleep X Firm provides unparalleled back support through two distinct features working together. First, the 13-gauge pocketed coil system is zoned, meaning the coils in the center third of the mattress are firmer for enhanced lumbar support. Second, a dedicated band of dense, copper-infused Talalay latex is placed strategically in the lumbar region on top of the coils, adding another layer of targeted, responsive support right where your body needs it most.

    What are the benefits of Talalay latex compared to memory foam?

    Talalay latex offers a different, often preferred, feel to memory foam. While memory foam slowly contours and cradles the body, Talalay latex is naturally buoyant and responsive, providing instant pressure relief with an uplifting feel so you never feel "stuck." Its open-cell structure makes it incredibly breathable and cool-sleeping. Furthermore, it's one of the most durable foams available, and when infused with copper like in the Sleep X, it becomes naturally antimicrobial.

    Do you offer financing options?

    Yes, at Mattress King, we offer a variety of financing options to fit your budget. Our partners include Synchrony, Affirm, and Snap Finance. Synchrony offers plans like 12 months with 0% interest for those with good credit. Affirm provides flexible payment terms, while Snap Finance is a great lease-to-own option for those with developing credit. You can explore and apply for these options to find the plan that works best for you.

    Do you offer delivery and old mattress haul-away services?

    Yes, at Mattress King, we provide convenient delivery services across Oklahoma. We pride ourselves on offering fast, one-day delivery options. For those who opt for our upgraded delivery service, priced at $99, we not only deliver but also set up your new mattress and haul away your old one. In addition to this, we offer a free delivery option that includes doorstep drop-off, similar to services provided by FedEx and Amazon. This option is great for those who prefer a contactless delivery to their front porch or door. For a comprehensive understanding of our delivery services and to find the best option for your needs, please visit our delivery information page here.