4.3 Cloud Visco Elastic Memory Foam out performs and relieves painful pressure points better than the leading competitor with innovative visco elastic memory foam technology and better formulation to help you sleep through the night without tossing and turning, allowing you to awake refreshed and renewed after a good nights sleep.Cloud9 Visco-elastic foam - memory foam - provides an ideal sleeping surface. In normal temperatures it is firm, but when you lay down to sleep it reacts to the temperature of your body and begins to mold itself to your shape. Weight is then distributed evenly along the surface, relieving pressure and helping you to sleep more soundly without tossing and turning. Cloud9 Memory Foam Contours perfectly and molds to your body, superior pressure relief reduces back pain, increased circulation for a deep sleep. They go right on top of your bed - very useful for making a firm, hard or old mattress much more comfortable. The "Featherlight Sleep System" will kindle a sincere delight when it's time to retire for the night. Our exclusive, "Featherlight" formula makes you feel like you are floating on CLOUD9, sailing forth into a sea of enchanted dreams. We usually recommend that if the person using the visco-elastic memory foam mattress pad weighs under 200lbs and they are just looking for added comfort they should get a 2" visco-elastic memory foam mattress pad, if they weigh over 200 we definitely recommend a 3" visco-elastic memory foam mattress pad and for those that weigh over 250lbs the 4" toppers are the best option for pressure point relief and comfort. The 3.3 Cloud9 visco-elastic memory foam is SUPER SOFT being less dense and having a softer compression or ILD rating. The 4.3 Cloud9 Topper is slightly firmer and provides a little more support while at the same time remaining soft and supple with a slightly more supportive compression or ILD. Our most luxurious 5.3 Cloud9 visco elastic memory foam is firmer than the 3.3 and 4.3 Cloud9.