Soothing vapors. Waterless. Releases Vicks vapors. SoftGlow nightlight. Non-medicated. Up to 8 hours per pad. Works by heat activating the soothing menthol vapors in the Vicks VapoPad and releasing them in the air. Guiding slots make it easy to insert and remove scent pads. Soft, glowing nightlight. Simply plug unit in for up to 8 hours of soothing comfort. www.kaz.com. UL listed for household use only.