Delta brainwave sleep therapy with insect (incl. mosquito) repellent ultrasound : Airplane

When we sleep, human brain emits certain kind of brainwaves in each stage of sleep cycle. The most important and longest stage in the cycle must be the deep sleep stage when your brain is resting with no dreams and in that stage, delta brainwaves are coming out. This sound helps to pull delta brainwaves out of you so that you can sleep deeper and tighter. It also includeds the 20kHz ultrasonic insects repellent sound (mosquitoes, ants, roaches, etc…) which is inaudible to human ear but protect you from bugs. Adjust the volume somewhere you feel comfortalbe. Do not use earphones or the bug-proof function will not work!

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공부할 때도 정말 유용해요😊 올리신 20kHz 영상들은 전부 벌레 퇴치에 동일한 효과라고 보면 되나요?