The Repose Memory Pocket 800 4ft Small Double Mattress has upto 800 pocket springs each moving independently to the movement & shape of the body for brilliant support. The 30mm layer of memory foam moulds to the natural contours of the body ensuring full body support. Air vents prevent body humidity & moisture buildup helping to keep you cool. Being non turn this mattress only needs to be rotated from end to end for great convenience.