2 in 1 Headphone Jack Adapter Aux Audio Headphone Stereo Jack,Dual Port Earphone Adaptor Connector Splitter Dual function :Supports data synchronization Supports the audio headset's remote control and microphone functions. Through the headphone changer to control the volume, play music and answer or end the call,Allows you to listen to music or phone while charging. Perfect design:The Double Port adapter allows you to charge Phone and play music at the same time. Powerful features :Supports incoming call + volume control + charging + music listening. (Note - The charging port symbol and the music gate symbol are distinguished.) This is a thoughtful and enjoyable design for any music lover, and now enjoy car music whenever and wherever possible.