Description: [Premium Quality] This Schumann wave generator is 7.83HZ very low frequency generator, which features high accuracy and stability. The premium material ensures its durability, precision with a long service life. [High Precision and Stability] The Schumann generator adopts high stable frequency acquisition elements including high stability pulse chip, precision correction capacitance and precision multi-loop adjustable resistor, in order to ensure the reliable performance. [Built-in 2000mA Lithium Battery] With rechargeable large-capacity lithium batteries, optimized for multiple power consumption, Very-low power consumption, and can work for about a years after being fully charged. [Convenient to Use] With work toggle switch, and work condition indicator (red, green or frequency flashing blue), you can clearly see its work conditions. [Great Help to Sleep] The Schumann wave can help create relaxed atmosphere, making people calm and comfortable. It helps to improve sleeping quality, relieve Sleep, relieve fatigue and restore physical and mental health. Specification: Working Time: About 1 year (full of electricity) Working Power: 0.3mW Working Mode: 7.83Hz very low frequency electromagnetic wave Size Chart: 100x100x13mm/3.94x3.94x0.51inch Package Includes: 1 Piece of Schumann Wave Generator 1 Piece of Type-C Cable Note: 1. Please allow slightly error due to manual measurement. 2. Due to the difference between different monitors, the picture may not reflect the actual color of the item. 3. Wish you a wonderful on-line shopping!