Easy to use for 2 users. Plug the transmitter into the smartphone (Lightning port) and press the switch keys simultaneously, the Lapel mics will automatically connect with the receiver Almost no transmission delay when using this mini microphone, which helps to synchronize background music and voice in real time, providing a better experience when watching videos without having to post-process. With the 2.4GHz frequency band and auto-sync technology, it prevails a first-class and clear sound, it also provides you a range of up to 60ft for stable and safe wireless transmission.