E-accexpert Cowboy Cap USB Mini Portable Air Humidifier, Black Easy-Fill bottle or cup with purified water, place the humidifier into the opening, making sure the filter is submerged, Then plug the humidifier into a USB port for instant comfort Portable-Small and light,The portable cool mist humidifier fit in your purse or coat pocket. Essential Oil Diffuser Aromatherapy Mist Maker. Powerful-Creates a soothing personal space at home, the office, in a car, or traveling Healthful-Provides relief all year long.Relieves cold, cough and flu symptoms, itchy dry skin, congested sinuses, chapped lips, dry eyes, & headaches by adding moisture to dry air. Safe-This environmentally-friendly humidifier helps reuse bottles and has a low power output of 5 watts.