Flexcell 500 single memory foam mattress. 2 FREE PILLOWS The Flexcell 500 range of memory foam beds amp mattresses are made with 5cm of high density visco elastic memory foam & an easy removable luxurious woven damask cover. This range is made with slow recovery memory foam supplied from UK market leader British Vita Foam & incorporates an open-cell technique for increased airflow. Each mattress has 5cm of finest top quality Visco elastic Memory foam.