Features: Use UHF frequency band, with strong anti-interference capability, wireless range up to 70m. Adopt DPLL digital frequency control technology, with 6 preset channels. Applied noise value control system, will auto mute if no signal; Use WNCR noise control technology, featuring extremely low bottom noise. Adopt a unidirectional lapel mic with high sensitivity and long pick up distance; Sent with a mini short mic. Adopt complex interference-free circuit, no mutual interference even you use more than 4 sets device at the same time. LCD screen display battery status, channels etc; 2pcs AA batteries can last for 15h. (Battery is not included.) Can be mounted on belt or camera easily; Lightweight for long time holding.