Mancini’s Sleepworld Onyx Firm Mattress 13″

Mancini’s Sleepworld Onyx Firm Mattress 13″ · Queen

The Mancini’s Sleepworld Onyx Firm Mattress 13″ is an innerspring mattress built for back sleepers and anyone chasing a firm mattress for back pain relief without losing the light body cushioning that makes firm beds livable. At 13 inches tall, it packs a meaningful coil system beneath structured foam comfort layers that work together to keep your lumbar in line while the gel-infused quilt layer takes the edge off pressure points at the hips and shoulders. The result is a mattress that sleeps genuinely firm without feeling punishing. If you want to put it side by side with every competing option at this price point before committing, stop by any Mancini’s Sleepworld location and a sleep specialist will walk you through exactly that.

COMFORT AND FEEL: Firm and lifted with a cool, lightly cushioned surface that supports without contouring deeply.

SIZE: This queen sized mattress is a strong fit for solo back sleepers and couples who both prefer a firm, non-sinking sleep surface.

BEST SLEEP MATCH: Back sleepers will get the most from this firm innerspring mattress. The pocketed coil system keeps the lumbar supported through the night, making it a natural fit for those who wake up stiff.

BEST FOR: Ideal for sleepers who need spinal support, run warm at night, or have been waking up with lower back tension on a softer bed.

CONSTRUCTION SPECIFICATIONS: The heavyweight stretch knit cover is cool at first contact and pulls heat away from the surface. A gel-infused memory foam quilting layer cushions the hips and shoulders without allowing deep sinkage. Firm and extra-firm high-density comfort foams underneath hold your body position steady. The 8-inch pocketed coil system with fabric wrapping isolates motion and keeps the spine aligned. A shock-absorbing base layer protects the structure over time. Foams are CertiPUR-US certified.

SETUP AND COMPATIBILITY: The Onyx Firm ships flat and is compatible with adjustable bases, platform frames, and traditional box springs. Professional in-home setup is included with delivery.

NOT A FIT FOR: Side sleepers who need deep pressure relief at the shoulder may find this feel too firm. Not the right fit for sleepers who prefer a plush or contouring surface.

YOUR SLEEP, BACKED BY US

Every mattress at Mancini’s Sleepworld comes with a 120-night comfort guarantee and our Rest Easy Promise. Visit any location to try this mattress in person before you buy, and ask about flexible financing to make it work for your budget. Adding a premium mattress protector at time of purchase upgrades your guarantee to a full 365 nights, giving you an entire year of certainty. Free next-day delivery and professional in-home setup are included, and our Best Price Guarantee means you will not find it lower elsewhere.