Nature&rsquo;s Sleep Thick AirCool IQ Cal King Size 3 Inch Thick 3.25lb Density Gel Memory Foam Mattress Topper with Microfiber Fitted Cover and 18 Inch Skirt Fitted Cover Fabricated from 100% Soft Polyester Microfiber The Nature's Sleep California King Mattress Topper is 3 inches thick and is constructed from 3.25 pound AirCool IQ Gel Memory Foam certified by CertiPUR-US Patented AirCool IQ Gel memory foam feels and performs like 5lbs memory foam Lighter foam visco-elastic technology contains larger open memory foam cells that react to the sleepers body increasing air flow, making the material exceedingly breathable Minimizes pressure points while sleeping on any mattress to relieve tossing and turning, and to reduce back, neck, hip and shoulder pain aches Includes a plush microfiber cover that slides over the topper and keeps your mattress protected and in place 3.25lbs of AirCool IQ Gel Memory Foam CertiPUR-US approved Plush 3 inches of gel memory foam Soft 100% microfiber cover Perfect for any type of sleeper: side, back, stomach