A few of my fellow CNET mattress experts and I got a behind-the-scenes look at a mattress factory's secret foam-pouring ...

The Casper One Foam mattress has a classic three-layer all-foam design, which is what we saw on the old models of Casper and beds from many other brands, including Nectar, Bear, Leesa and Nolah.

Mattresses 6"-10" thick feature two layers of foam, a larger base of high-density foam for stability and support, and a smaller (roughly 2") layer of gel swirl memory foam to adapt to your body ...

Gel-infused memory foam: This 2-inch layer of gel memory foam is designed for pressure relief, soft contouring and a plush feel. Plus, the gel infusion helps minimize heat retention.