California King 4 Inch Thick, 2.5 Pound Density Visco Elastic Memory Foam Mattress Bed Topper Made in the USA Instantly makes any mattress more restful, comfortable, and supportive in sagging areas of mattress 4 inches of soft yet supportive 2.5 lb memory foam conforms to your body Made in the USA using enviromentally friendly processes. PURGreen Certified. Memory foam reduces pressure points that cause you to toss and turn, so you sleep better. Topper features a two and a half-pound density and a medium gel-like feel