The Black Diamond Rockwell is Diamond Mattress's luxury extra-firm hybrid: a 16-inch build with Coolstream fabric on top, high-density titanium memory foam plus Ice Flex cooling bands in the middle, and a 9-Series wrapped coil system anchoring the support. 5-pound high-density charcoal memory foam adds odor control and a denser feel than typical hybrids. 20-year warranty, made in California.
Coolstream fabric + Ice Flex cooling bands + titanium memory foam — engineered, not a marketing claim.
More coils per square foot than typical 7-Series hybrids — denser support that doesn't sag.
High-density charcoal layer for odor control and longevity.
Tall, dense build engineered to outlast — backed by a 20-year warranty.
A 10/10 firmness — supportive top with minimal contour. Best for back and stomach sleepers, plus heavier sleepers who want less hug.
Built for adaptive support and breathability. Every layer is hand-checked before it ships from our warehouse.
The Black Diamond Rockwell is a luxury extra-firm mattress built for heavy sleepers — a 16-inch hybrid at the top of Diamond Mattress's lineup, engineered around three distinct cooling systems and a 9-Series individually wrapped coil core, finished with a high-density 5-pound charcoal memory foam layer for longevity and odor control. Backed by Diamond Mattress's 20-year warranty.
Extra firm — a true 10 / 10 on Diamond's scale. That's the build back and stomach sleepers reach for when other hybrids let the hips drop, and the configuration heavier shoppers tend to land on for long-term stability. The three-layer cooling stack (Coolstream + Ice Flex + titanium) is engineered for the kind of hot sleeper who has tried "cooling" mattresses that didn't deliver. Strict side sleepers should look at the Dreamstage 2.0 Arise Luxe Plush instead — an extra-firm surface is too unforgiving at the shoulder.
Twin, Twin XL, Full, Queen, King, and California King. Queen from $2,599.
Yes — free white-glove delivery anywhere in Los Angeles on orders over $499, including setup and free haul-away of your old mattress. Order by 4pm for same-day delivery.
You have our 120-night comfort exchange. Sleep on it for at least 30 nights, and if it isn't right, exchange it for another mattress — we handle the pickup and redelivery.
It's covered by a 20-year manufacturer warranty against defects, and we file warranty claims on your behalf.
Yes — 0% APR financing through Synchrony on approved credit, plus Acima lease-to-own with no credit needed. Most applicants are approved in minutes at checkout or in any showroom.
Yes — our Los Angeles showrooms in Koreatown, West LA, La Brea, Studio City, and Glendale carry our lineup on the floor. Walk-ins welcome, no appointment needed.
