WarmlyYours ClearlyYou Mirror Defoggers transmit gentle warmth across the mirror's surface, preventing moisture from forming while you bathe or shower. Self-adhesive backing allows easy application to any wall-hung mirror in just minutes. ClearlyYou Mirror Defoggers come ready to install in several shapes and sizes. This 12” X 18” rectangular mirror defogger is ideal for smaller mirrors or for clearing a specific focal point on a larger surface. Pre-attached power leads conveniently connect to your bathroom's 120V lighting circuit. The mirror defogger draws only a minimal amount of energy and operates at a constant, regulated temperature of 104 degrees. Not suitable for installation in the shower.