20cm deep sleep design memory foam mattress44 complete with free fully washable luxury maxicool removable temperature regulating cover46space 45age technology originally developed by nasa for use by astronauts46 vacuum packed into an inner and outer quality box46 high density memory foam is heat 38 pressure sensitive44 adapting perfectly to the shape of your body46 firmness rating medium to firm46 flame retardant 40bs5852 standard41 and hypoallergenic46 king