Use it for: instant relaxation, deeper meditation, improved sleep, and frequency transmission. 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. – 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 ~ 30,000Hz Pure Sine Wave Signal voltage amplitude: 3V With 3.5mm output With acrylic shell Size: 155 x 105 x 26mm (with shell) Weight: 300g (with shell) Product List: 1pc Custom Frequency Generator V2 (with acrylic shell)