Crane USA Warm Mist Humidifiers, Grey BACTERIA-FREE WARM MIST: increases air moisture for easier breathing and a good nights sleep WHISPER QUIET: Runs up to 24 hours, misting 3.5 gallons of moisture per fill AUTO-OFF FUNCTION: activates when water tank is empty CLEAN CONTROL ANTI-MICROBIAL MATERIAL: proven to help reduce mold and bacteria growth up to 99.96%* 1 GALLON TANK: Removable 1 gallon tank easily fits under most bathroom sinks VOLTAGE  120 V, for domestic use only