--SMART HUMIDIFICATION / LARGE CAPACITY: 5.5-liter water tank works for rooms up to 500 sq ft & lasts up to 40 hours of continuous operation at 1 refill. Smart humidification system includes 3 types of humidity control: auto mode, constant humidity level & 3 speed options. Cool & warm (up to 140°F!) mist for around-the-year comfort. Cold mist reduces dust and statistic electricity. Warm mist relieves stuffiness and cold symptoms. Create a heаlthy livіng space in a professional way!