7.83Hz Schumann Waves Frequency Generator Adjustable 0.01Hz~100000Hz Signal Gene

DC 5V 0.01Hz~100000Hz Adjustable Frequency 7.83HZ Schumann Wave Generator Sine Wave Signal Generator Micro USB Interface. 1X Schumann wave generator module. Default frequency: 7.83Hz. High quality material: High transparency acrylic shell, beautiful and durable, moderate size, easy to place and carry.

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