Avoid slight current generated by bare foot contact with the ground. No Adapter ! Use your cellphone Adapter to supply this product or connect with computer. USB 5V boost circuit low-voltage power supply technology to prevent harm to the human body and solve problems such as regional power supply, vol tage differences, and transformer mismatch. Built inlow-passfiltering circuit design, fullv filtering ou external audio equi pment noise. Four sets of balanced power supply and balanced input and output signals ensure stable voltage balance and suppress common mode interference.