Check the listing for details. 2 Pack Adjustable 0.1HZ-30KHZ For Schumann Wave Frequency Pulse Generator US. Condition: New. Listed at 17.55 USD. Description: Wave itself is not directly acting on the sound or video products to improve the sound quality, but the role of the spatial environment, so that the human body and mind to relax, improve the body's perception of sound and images, improve the body's health work efficiency and relieve psychological stress also has a better effect. The product not only can output 7.83Hz wave, but also can adjust the frequency in the range of 0.1Hz ~ 30KHz, digital circuit crystal oscillator frequency reference, more stable, stronger anti-interference. Product features:1. using high quality materials, the product has good frequency stability; 2. This product can not only output 7.83Hz wave, but also join the programmable FM technology, can adjust the frequency in the range of 0.1Hz~30KHz; 3. 2 specifications can be selected according to demand, red square wave non-adjustable frequency fixed at 7.83Hz, green standard models 0.1Hz ~ 30000Hz various frequency can be adjusted; 4. digital circuit crystal frequency reference, more stable, stronger anti-interference; 5. Power supply interface using DC5.5 * 2.1 interface, easy to use, USB end plugged into a rechargeable battery or USB charging head or other USB powered devices can work. Product parameters: Green standard model:Circuit board size:15*15cmAntenna waveform: sine waveInterface waveform: sine wave + square wave + inverted square wave (the lower left corner is the output interface, waveform output at the same time)Power supply interface: DC5.5*2.1Power supply voltage: 5VRated power consumption: