1. The Schumann wave is an extremely low frequency electromagnetic wave that can penetrate various materials and is non-ionizing radiation. 2. The Schumann wave is a naturally occurring phenomenon and represents a continuous background frequency present in the Earth's atmosphere. 3. This device is designed to generate a frequency that corresponds to the natural resonant frequency of the Earth's ionospheric cavity, which may support general well-being. 4. The generator simulates a 7.83 Hz frequency using electronic circuitry, producing a sine wave via a programmable intelligent chip. 5. The device is intended to emit a stable and consistent frequency to support environmental balance and may help reduce exposure to surrounding electromagnetic fields. Specification: Item Type: Schumann Wave Generator Power Supply: Built-in Lithium Battery Micro-USB Charging, with 4-level Battery Indicator Power Consumption: 5V 0.08A Working Frequency: 7.83Hz, generated as a sine wave by a programmable intelligent chip. Waveform, frequency, and output are preset by default, offering high frequency accuracy and stability. Additional USB-A Port for External 5V Power Supply Size: 80 x 76 x 24mm / 3.15 x 2.99 x 0.94in Color: White Material: PU + Plastic Package Contents: 1 x Schumann Wave Generator 1 x USB Cable Note: Light and screen display differences may cause slight variations in color between the image and the actual item. Measurement allows an error of +/- 1-3cm.