Extend Length You Want: This 4 Pole headphone extension cable with Microphone Function which can extend your devices with 1.5mm jack to the desired location for Audio & Mic. It can easily extend the connection between your iPhone, iPod, MP3 players, smartphones, tablet or any other 1.5mm aux port equipped devices to your headphone, earphone, speaker, car stereo or home theater system, etc. NOTE: Compared with the TRS extension cable, it supports the Function of Microphone