Replace your old mattress with a breathable gel layer right away! Erdoru memory foam mattress toppers instantly add a comfort layer to your mattress to improve comfort. Not only does our topper provide ideal sleeping conditions, the memory foam also provides pressure relief. As you lie down, the gel-filled memory foam topper begins to fit your body, releasing pressure where it's needed and distributing your weight evenly. The cooling gel also regulates your body's temperature by trapping and distributing heat, giving you a cooler sleeping environment than traditional memory foam. The foam is certified by CertiPUR-US to meet quality standards.Available in 2-inch and 3-inch heights and sizes: (inches L x W x H) twin (74 x 37.5 x 2/3), Twin XL (79 x 37.5 x 2/3), Full (74 x 52.5 x 2/3), Queen (79 x 59 x 2/3), King (79 x75 x 2/29).