Use it for: instant relaxation, deeper meditation, improved sleep, and imprinting frequencies onto objects. How to use: Plug the device into a wall socket, laptop, or power bank using the provided USB-C power cable. Connect headphones to the device or connect the device to a speaker using an AUX cable. Enter the desired frequency using the touchpad on the device, then press OK. Specifications: Working voltage: DC 5V (DC 4-15V) Working current: 9-14mA Power interface: Type-C (supports Type-C to Type-C power supply) Default frequency: 7.83Hz Adjustment range: 0.01Hz to 30,000Hz, pure sine wave Signal voltage amplitude: 3V Equipped with 3.5mm audio output Housed in an acrylic shell Dimensions: 155 x 105 x 26mm (with shell) Weight: 300g (with shell) Package includes: 1 x Frequency Generator (with acrylic shell) 1 x USB cable