Adjustable Portable Travel Humidifier: Ultrasonic cool mist humidifier allows you to change the length of item body as you like.When you are staying in a hotel, working, studying or drinking coffee, you can use mugs or small glass containers by a short swab to work.When you're relaxing, driving, traveling, or yoga, you can use a large container or mineral water bottle to work with a long cotton core. Note:Mineral water,cold boild water and clean tap water are the best for the humidifier.Please note do not add Essential oils into the water tank. Leakproof: The bottle mouth made of rubber, which can leakproof when the bottle was tumbling. Note: Do not stand upside down 180 degrees for a long time. Automatic Shut-Off: Click the button(blue light on),4 hours automatic power-off;Click the button again(red light on),8 hours automatic power-off. Click the button a third time to turn off the spray. Simple Guide to Use The Humidifier: Step 1:Choose a container of appropriate length and a cotton swab, pour water into it and soak the cotton swab for 5-10 seconds. Step 2:Put the soaked cotton swab into the humidifier tube. Step 3:Put the small humidifier in the container and plug in the USB cable. Step 4:Press the open button on the humidifier for a short time, then enjoy yourself! Size: 84*47*233 mm