1. Using high-quality materials, the product has good frequency stability; 2. This product not only outputs 7.83Hz Schumann waves, but also incorporates programmable frequency modulation technology to adjust the frequency within the range of 0.01Hz-100000Hz; 3. Digital circuit crystal oscillator frequency reference, more stable and stronger anti-interference; 4. The power interface adopts DC 5V interface, which is easy to use. The USB end can be plugged into a power bank, USB charging head or other USB powered devices to work. Product Description: Shumanbo itself does not directly act on sound or video products to improve sound quality, but rather acts on the spatial environment to relax the body and mind, enhance the body's perception of sound and images, improve the efficiency of human health work, and relieve psychological pressure. This product can not only output 7.83Hz Schumann waves, but also adjust the frequency within the range of 0.01Hz to 100000KHz. The digital circuit crystal oscillator frequency reference is more stable and has stronger anti-interference ability. Parameters: Supply voltage: DC5V Default frequency: 7.83Hz Adjustment range: 0.01Hz-100000Hz Colour:Green & Transparent Material:PCB+Plastic Package Contents: 1 * Schumann wave generator(with housing) 1 * USB cable(USB cable color is random, no specification is accepted) Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.