1. USB-powered (typical: +5V @ 0.1A); includes a USB cable. 2. Features an imported main control IC with ultra-low quiescent power consumption, ensuring a more stable waveform. 3. Outputs a 7.83 Hz pulsed sine wave with a 50% duty cycle; the frequency can be finely tuned for calibration. 4. Constructed using materials, ensuring guaranteed product quality. 5. Features an exquisite and compact design that is highly portable. Antenna Waveform: Sine Wave Interface Waveform: Sine Wave Power Interface: USB Default Frequency: 7.83 Hz Color: Black Material: Acrylic Package Contents: 1*Schumann Resonance Generator 1*Cable 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.