It uses 35D to add softness to your mattress.
3 Inch Mattress Topper Pad Gel Infused Memory Foam Mattress Topper Twin The bamboo cover is equipped with anti-slip mesh backing to prevent sliding and premium metal zipper for easy removal and washing.This will be your most cost-effective choice HIGHLY BREATHABLE: Plush 3 inch memory foam topper is infused with gel to help regulate temperature so this topper sleeps cooler than a regular memory foam topper.