Features 1、7.8HZ GENERATOR: Ultra low frequency Schumann wave generator, resonant frequency 7.8Hz (adjustable), with high accuracy and good stability. 2、EXCELLENT PARTS: Adopts highly stable pulse chip, precise correction capacitor and precise multiple loop adjustable resistor, with high reliability. 3、LARGE CAPACITY: Can be used after charging, the rechargeable large capacity lithium battery can last for about 400 days after being fully charged. 4、MAIN PURPOSE: Help people relax physically and mentally, improve perception of sound and images, reduce stress, and improve work efficiency. 5、GOOD PERFORMANCE: The generator adopts excellent PCB components to ensure stable performance, less interference and longer service life. Specification Item Type: Schumann Wave Generator Material: PCB Resonance Frequency: 7.8Hz (Adjustable) Package List 1 x Schumann Wave Generator