The construction of this cushion assists in the reduction of pressure to the user's vulnerable bodily points and areas, whilst providing stability and shock absorbtion. A three layer combination of visco elastic memory foam and high density polyurethane foam make this seating appliance extremely durable and effective. Will help with the reduction and prevention of pressure sores and ulcers. Memory foam ensures muscles are relaxed and tension relieved. Supplied with Harley Premium Dartex waterproof / VP cover. Other cover options available. Suitable for patients up to hgh risk (with appropriate nursing care).