Non45sprung mattress20mm memory foam sits on top of 140mm high rebound pu foamanti45bacterial reflex foam increases resistance to dustmites and bed bugseasy45rotate systemnon45slip baseplease note58 the mattress is delivered vacuum packed and will fill out to it39s full size once opened mattress is non returnable once removed from its packaging due to health and hygiene your statutory rights are not affectedr dimensions single w97 l2005cm double w1435 l2005cm king w