10 Year Warranty

New for 2017, the Comfortec Shelton Firm mattress is much more affordable than the bed-in-a-box options out there and offers the kind of sturdiness and great craftsmanship of the beds from long ago. Heavy duty foam encasment, dense foam layers and a company that produces its own foam are all contributing reasons why. The All-Natural Cotton Cover is an added plus. Don't let the low price tag fool you; the Shelton Firm is a very nice mattress.

The trademarked coil system ("Spectrum" by Symbol) is said to be significantly stronger than the ever-popular Pocketed Coil units out there and, it still contours to the individual sleeping on it very well.  This particular unit also offers 30% more springs in the middle-third of the mattress for strength and support where you need it most - in your lumbar region. An Insulator Pad helps to keep foam layers from dipping into the springs, over time. A Convoluted Extra Firm R65 layer provides not only support but breathability within the mattress; because, no one likes a hot sleep.

A great value and surely destined to become one of our best sellers, this is a great traditional-feel firm mattress that is 100% Made in the USA.

Roll on to zoom pic

 Other Views:
  traditional firm mattress affordable luxury american made cotton cover   firm mattress specs specifications inside mattress american made offest coil low gauge   mattress features convoluted foam spectrum offset coil unit foam encasement natural cotton cover

Shelton Firm Mattress

SALE reg.
Twin $450 $700
Twin XL $520 $775
Full $575 $925
Queen $599 $1,000
King $925 $1,400
Cal King $1,120 $1,600
Other sizes

free shipping

Mattress Scale
semi firm mattress
Approx. Height of Set: 19" (Matt 10.0" Base 9")

This Mattress Features:

CertiPUR-US certified foams are:


✓ Made without ozone depleters
✓ Made without PBDEs, TDCPP or TCEP (”Tris”) flame retardants
✓ Made without mercury, lead, and other heavy metals
✓ Made without formaldehyde
✓ Low VOC (Volatile Organic Compound) emissions for indoor air quality (less than 0.5 parts per million)
✓ Made without phthalates regulated by the Consumer Product Safety Commission


Natural Cotton Cover
FR Fiber Barrier
3/4" Symbol Foam

Mattress(Top Side)
3/8" Symbol Foam
2" Convoluted Extra Firm R65 Foam
Insulator Pad

540-Spectrum Tri-Zoned Coil Unit, Foam Encased
2" Symbol Support Core


10 Total Years (10 full)

Shelton Firm Mattress

The Comfortec Shelton Firm is one of the latest offerings from Symbol Mattress. Its "Spectrum" coil unit is designed to surpass other coil units in terms of durability. In addition to the springs' increased strength, the "540 Spectrum Tri-Zoned" also contours to the body a considerable amount. Despite this mattress having some of the most advanced features in the industry, it's a very affordable model. This we definitely like!

Even Symbol's foams are manufactured in the United States; not imported like the foams used by nearly every other maker of mattresses. Another indicator of quality craftsmanship is the sheer weight of this mattress. While not immovable and not overly massy, for a ten inch thick mattress - the Shelton Firm has a healthy amount of weight to it. This is undoubtedly due to its 13.75 gauge steel coils and its 4" thick high density foam encasement.

For a firmer sleeping surface that's not quite as hard as the floor (though, we carry one that hard) but that is great for both back and stomach sleepers, the Shelton Firm may be the right mattress for you! Also available in custom sizes for RVs, boats, antique beds and more.


Scroll down to read or write reviews


  • Shipping or delivery of this item to most areas within the 48 contiguous states only. We cannot offer delivery of this item to Alaska, Hawaii, US Territories or APO/FPO addresses without added charges. Please call customer service for rates and availability.
  • Nationwide and "free" rates are valid to most cities in the continental US. Destination must be accessible by large truck. Some locations may have a small surcharge.
  • For complete details, read our Shipping and Return policies.
  • Please call customer service for returns.

For local delivery rates and polices, check the Delivery Page



Related items:
Mid Profile 7" High Standard 9" High Split Box Spring 9" High KD Foundation
Fits in tight locations

7" high box springs

Mid Profile Box Spring Foundation

Starting at:
Reg $120
Sale $74

Standard box springs

Standard Box Spring Foundation

Starting at:
Reg $150
Sale $89

Split Box Spring King Queen FUll

Standard Split Box Spring Foundation

Starting at:
Reg $220
Sale $140 / 2 pc set

Free shipping
Nature's Sleep KD Foundation

Nature's Sleep
Knock Down Box Spring Foundation

Reg $199
Sale $184