The stationary [Mosout Dual Sonic H1] is an item that generates light and sound that insects don't like. The speaker emits a double "Moth Dual Sonic" of special ultrasonic waves that cannot be heard by the human ear, and "Moth Sound", an audible sound wave that can be faintly heard by the human ear but is more disliked by insects. In order to prevent insects from getting used to the sound, it is randomly emitted at intervals of 0~0.5 seconds. It emits a sound pressure of 80db or more in the frequency band of 20kHz~100kHz, and is very useful as an "invisible shield" for people who do not like insects.