Maximum Support and Lift, with Memory Foam at the Surface
The Serta Perfect Sleeper® Cascade Range Extra Firm Mattress is the firmest feel in the 2026 Perfect Sleeper® lineup. The 14" profile is built on higher-density 920 Q4™ linked coils and 5 Zoned Comfort, topped with QuiltLoft™ Memory Foam and a CoolFeel® Plus cover with breathable wool.
Extra Firm Comfort, Explained
Extra Firm is structured and strong with minimal give, so your body stays on top of the mattress instead of sinking in. That lift helps keep the hips from dipping below the shoulders, a common cause of morning back stiffness for stomach and back sleepers. A quilted memory foam layer takes the edge off the surface so firm never feels hard.
What's Inside the Cascade Range Extra Firm
Layer diagram for this exact model.
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1Q4™ Support System
920-density 4-in-1 coils are linked together to spread your weight evenly and deliver long-lasting support, surrounded by BestEdge® Foam Encasement for stability. -
25 Zoned Comfort
Alternating firm and plush zones are designed to hug the curves of your shoulders, back and hips, adding support where the body naturally curves. -
3QuiltLoft™ Memory Foam
A conforming memory foam quilted right into the top layer, so pressure-relieving contour starts at the surface. -
4CoolFeel® Plus Fabric with breathable wool
Serta's upgraded cooling cover fabric paired with a breathable wool layer for a refreshing, cool-to-the-touch feel.
CertiPUR-US® Certified foams · Made in the U.S.A. with global components
Why You'll Love It
Designed to Ease Aches
Zoned coil support and pressure-relieving foams are designed to help relieve aches and back pain by keeping your body in natural alignment.
Sleeps Cool
CoolFeel® Plus Fabric and a breathable wool layer help regulate temperature, while the coil core lets air move through the mattress.
Built to Last
Linked 4-in-1 coils share the load evenly across the bed, helping reduce sagging and body impressions over time.
Classic Innerspring Feel
A responsive, on-top-of-the-bed feel that's easy to move on, with the airflow and bounce people love about coils.
Support Where Your Body Needs It
Your shoulders, hips and lower legs press into a mattress the most, while the lower back and upper thighs need extra lift. 5 Zoned Comfort answers both, with plusher zones where you press in and firmer zones where you curve, so the Cascade Range Extra Firm keeps your spine aligned from head to toe.
Choose Your Cascade Range Feel
Compare the Perfect Sleeper® Collection
| Series | Type | Coils | Comfort Layer | Cover | Feels & Heights |
|---|---|---|---|---|---|
| Cascade Ridge | Innerspring | 860-density Q4™ | PillowSoft® Aire Foam | CoolFeel® Fabric | Plush 12.5" |
| Cascade Canyon | Innerspring | 860-density Q4™ | PillowSoft® Aire Foam | CoolFeel® Fabric + wool | Firm 13", Medium 13", Plush 13.5", Medium Pillow Top 14", Plush Pillow Top 14" |
| Cascade RangeTHIS SERIES | Innerspring | 920-density Q4™ | QuiltLoft™ Memory Foam | CoolFeel® Plus Fabric + wool | Extra Firm 14", Medium 14", Firm Pillow Top 14.5", Plush Pillow Top 15" |
| Cascade Bluff | Hybrid | 920-density Q4™ | EverCool® Supreme Memory Foam | CoolFeel® Plus Fabric + wool | Medium 13.5", Firm 14.5", Plush 14.5" |
Every model shares Serta's Q4™ Support System, 5 Zoned Comfort, BestEdge® Foam Encasement and a 10-year limited warranty.
MATTRESS DIMENSIONS
14" high
14" high
14" high
14" high
14" high
14" high
14" high
*Dimensions are approximate and may vary slightly. Split King ships as two Twin XL mattresses.
SPECIFICATIONS
| Brand | Serta® |
|---|---|
| Collection | Perfect Sleeper® (2026) |
| Series | Cascade Range |
| Model Number | 500303921 |
| Feel | Extra Firm |
| Mattress Height | 14" |
| Mattress Type | Innerspring (tight top) |
| Support System | 920-density Q4™ Support System, 4-in-1 linked coils |
| Zoned Support | 5 Zoned Comfort |
| Comfort Layer | QuiltLoft™ Memory Foam |
| Edge Support | BestEdge® Foam Encasement |
| Cover | CoolFeel® Plus Fabric with breathable wool layer |
| Recommended For | Back and stomach sleepers who want maximum support |
| Foam Certification | CertiPUR-US® Certified |
| Origin | Made in the U.S.A. with global components |
| Compatibility | Adjustable bases, box springs, traditional frames, platform and slatted frames, bunky boards |
| Warranty | 10-year limited warranty |
CARE
- Use a mattress protector to guard against spills and stains and extend the life of your mattress.
- Don't apply liquids or cleaners directly to the mattress; moisture can stain the fabric and break down the foams.
- To freshen a soiled area, sprinkle baking soda, let it stand about 15 minutes, then vacuum. Repeat as needed and air the mattress out.