Features: 7.83HZ extremely low frequency pulse generator helps to improve sleep, relieve fatigue and restore physical and mental for health. Imported ultra-low static power consumption master IC is adopted, and the ultra-low frequency pulse ripple frequency is more stable. Output 7.83HZ pulse, duty cycle is 50%, frequency can be adjusted and corrected, and it has the characteristics of high precision and good stability. Mini USB port power supply, generally +5V 0.1A, comes with USB cable. It can improve the human body's perception of sound and images, improve the efficiency of work creation, and have a good effect on insomnia and mental stress. Specifications: Product Name: Pulse Generator Material: Printed Circuit Board Power Supply: for DC 5V Current: 0.1A Square Pulse: 7.83Hz Size: Approx. 8x5.3x0.6 for cm/3.14x2.08x0.23 inch USB Cable Length: Approx. 30 for cm/11.for 81 inch Package Includes: 1 Piece Ultra-low Frequency Pulse Generator 1 Piece USB Cable note: Please allow 1-2cm errors due to manual measurement,pls make sure that you do not mind before you order. Due to the difference between different monitors, the picture may not reflect the actual color of the item.