ULTRASONIC COOL MIST TECHNOLOGY: Adopted Ultrasonic Cool Mist Technology, No noisy voice. It will not interfere with your sleep or work, with environmentally friendly material.HELPFUL FOR YOUR HEALTHEffectively improve indoor air condition. Increase humidity and also help prevent dry and chapped skin in dry seasons with no noise, lift your spirits and relieve stress.AUTO SHUTDOWN TECHNOLOGY: No Built-in Battery, USB Powered. 4 hours automatic power-off protection. When the water runs out, it automatically stops running.EASY TO USE: Open the silicone cactus top, pour the pure water into it (The capacity of the humidifier is up to 160ml), close the lid, connect it to PC, mobile battery, etc. with a USB cable and press the button.SUITABLE FOR ANY OCCASIONCute cactus shape and vibrant color will bring happiness to your room, desk, office, car. It will be a fabulous Christmas or birthday gift for your relatives, friends and colleagues.