grace & stella's hot + cool gel bead sleep mask soothes and adds comfort to your eye area. The microwave-safe beads can be heated up or cooled down in the refrigerator to fit your liking. When the mask is cool, it can help with tired, puffy eyes and wake you up when you need it. When warm, our mask aids in getting a relaxing night's sleep as well as reducing any congested sinuses and increasing blood flow to your eye area. The super soft, plush backing makes it super comfortable on the eyes. No uncomfortable, cold, hard plastic here!