Cover Material: A deep micro quilted hypoallergenic mattress with a four way stretch fabric for extra comfort. Memory Foam Mattress: Get a grey supreme memory foam mattress. Mattress Depth: Nine to ten inches thick with responsive 40KG/M3 memory foam to mould around the shape of your body. Open Sprung Mattresses: Features a 13.5 open coil bonnell spring to provide even support for all of your body's pressure points. Firmness: Has a medium firmness, perfect for people who like to sleep on their side. Sizes: Comes in six sizes that are suitable for any standard sized bed base (see full details for dimensions). Supreme Memory Foam Mattress | Grey | Small | Living Social