Night Therapy Elite 2.5" MyGel Mattress Topper - Queen Cover of yarn dye jacquard features a zipper for easy removal and is machine washable. Sleep cool layering system-2.5" MyGel infused gel premium memory foam. A leader in research, Night Therapy treats all of its products with green tea, a natural odor protectant. The comfort of your sleep environment is balanced with ingredients that are safer for you and the environment we all share.