Performance And Advantages 1. LED indicator light show the working status. 2. Support for common speaker or headphones. 3. Free to switch speaker and headphone modes. 4. Directly use USB port, universal plug and play. 5.USB External Driver-free Sound Card 6.Extending 3 Output Ports through one USB port 7.Adjustable Volume. With one external volume adjustment button, easy to control the volume according to your needs. 8.Wide Compatibility, Support TRS / TRRS mode. Tips: The standard of the microphone is OMTP, part of the microphone can’t working if the standard is CTIA, Such as iPhone earphone and the Three-piece headphones.