Feature: 1.Wire harness connected, no interference nor loss of sound quality. 2.Plug & play,convenient to use. 3.Hands-free phone call (HFP) and A2DP playback: supports Answer/Hang up/Reject/Re-dial etc., via car radio buttons and steering wheel or remote control box. 4.USB music and 3.5mm Aux Input: support USB or SD card and any external audio sources. 5.Easy Charge: offers 5V/1A standard USB charging port.