NOTEDo not use essential oils, perfume, distilled water, filtered water which will cause the cotton swab to clog and the Humidifier to be unusable. Please make sure the cotton core has soaked a few minutes before you turning it on.PORTABLE MINI HUMIDIFIERPortable and small design (3.74*5.07inch) is very easy take with you anywhere and super perfect for travel, bedroom, office, which is effectively moisturize dry skin and help you reduce skin peeling.TWO MIST MODESThis mini humidifier has two modes. When you press the button first time, it will continuously spray for 6 hours. When you press again and it will intermittently spray (stop 2 seconds) for 12 hours. 500ml large capacity produces longer mist.SAFE & AUTO SHUT-OFFThere is built-in water level sensor inside that will automatically turn off the power when the water is lower than the safe water level. And the seal is strong,no longer afraid of pouring liquid to leak in accidence.ONE BUTTON CONTROLThe portable usb humidifier is very easy to operate. One button controls for all functions, you simply need to press one button to set the mist. Make your life easier!