The anniversary memory support revo foam mattress features layers of revo foam the 4th generation in foam technology and the successor of the uks current favourite memory foam benefits includebreathabilitywide open cells with thicker walls for enhanced durabilityairflow is 30 times greater than a premium visco elastic mattress4th generation technologyresilienceoptimum comfort and support through the use of highly resilient high density full depth revo foam technologytested to bs en iso 83