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King Koil Sleep Product | Dover Firm Mattress

Product Information

King Koil Mattresses contain Lumbar Memory Foam / Lumbar Latex Foam, 5-zone Convoluted Foam, Superior Foam Encasement, Cool Gel Memory Foam. A King Koil mattress is specially designed to give you the best night sleep possible. Why is King Koil best premium bedding value? Because of advanced quality engineering, awarded patents by the U.S. Government, earned the prestigious mattress design award, industries strongest warranty honored worldwide, and handcrafted with attention to every detail since 1957.

Made in the USA with 100% American components. Environmentally friendly soy-based foams that are certified as CertiPUR-US. Amish-made wood foundations.

Price and sizes available

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Contour Layers

  • SafeGuard
  • 1 inch Everlast Quilt Foam
  • 1/2 inch Polyurethane Foam
Therapedic Backsense

Comfort & Support Layers

  • 1 1/2 inch 5-Zone Plush Perfect Contour
  • Lumbar Memory Foam

Support System

  • 5-Zone 805 Contour Coil
  • Superior Foam Encasement

10 Year Warranty. Minneapolis, MN

Our exclusive HourGlass polypropylene insert increases support and firmness by 18% at the shoulders & hips and 13% at the lumbar area. This flexible technology can be combined with virtually any coil unit to offer improved performance and added value at any price point.

  • Exclusive, enhanced support grid increases firmness in critical areas.
  • Open spring design provides progressive resistance as weight is applied, improving support where body weight is centered.
  • Zoned coil configuration allows for the density of coils to vary across the sleep surface in order to offer tailored support to every part of your body.

Maintain proper spinal alignment

Research has shown that anatomically correct support for your spine helps keep your back healthy and can have therapeutic benefits.

To maintain proper spinal alignment, our HourGlass Back Support® System provides zones of support for the different regions of your spine. This allows you to rest in a completely neutral position for optimum rest and recovery.

Unique Coil Design

These zones of support are further enhanced by our patented reactive coil design. As weight bears down on individual coils, they respond with increasing support. The result? By conforming to the shape of the body and providing balanced support from head-to-toe, our Dover mattress gives you the uninterrupted sleep you need.

Alternating coil design

Standard innerspring designs have a tendency to lean under pressure, causing unwanted motion transfer. Our unique, alternating coil design reduces motion transfer while still offering restorative support for a sound sleep.

Extra comfort layers Dover mattresses feature extra comfort layers made with latex, visco elastic or convoluted polyurethane to provide additional pressure relief and further reduce the effects of “tossing and turning.”

TheraFoam® encasement Improves stability while increasing the usable sleep surface by eliminating "roll together" and border breakdown.

Exceptional Warranties

Last, but certainly not least, every King Koil product is backed by the best warranty available. You’ll get a better night’s sleep knowing that you’ve purchased one of the world’s finest mattresses, which is supported by a worldwide warranty.