Fine Particles - This device can create 2-3μm fine mist which can penetrate into the upper & lower respiratory tract and bronchus to absorb small particles better. The medicine cup and device are detachable that is easy to clean and replace. Low Noise & Mini Size - The noise is lower than 25dB, creating a quiet and silent environment. Let the child feel relaxed and free and enjoy the process. It is portable and lightweight(weight:0.23lb) and palm-size(dimensions:2.4×1.77×4.76inch), very convenient to carry outside. Two Ways Charge & Auto Cleaning - This machine works by plugging it into a USB cable, or you can put two AA batteries in it(The batteries are not included). After use, you can press and hold it for 5 seconds to access automatic cleaning mode. Very easy to clean it up. Waterless Detection Technology - Designed with waterless detection technology, it is safer for kids when they use it. It will shut off when there is no water and avoid breaking the mesh plate. Fewer Residues - The solution cup reaches up to max 8cc. After use, the residues are less than 0.1ml. Removable parts are very easy to clean.