Shop name:Chong Qing Shuo Yue Ke Ji You Xian Gong Si Description: Our small and compact system requires no complicated setup and wireness as long as you put them on the same channel, transmitter can match multiple receivers. Because it automatically pairs the transmitter and receiver when powered on. Up to 5 systems can be used at the same time. Specification: Frequency range: 570-590MHz Adjustable channel: 16 adjustable frequency points Channel Spacing: 0.5-2.5MHz Modulation : DQPSK Frequency stability: 3PPM Frequency Response: 40Hz-20KHz Working range: 50-80M Built-in battery: 800mah Duration: 7 hours of battery life Antenna Impedance: 50 Sex to dry ratio: 110dB Operating voltage: built-in 3.7V Supported microphone types: dynamic microphones and 48V condenser microphones. Material: abs+metal colour: grey Package Contents: 1 x receiver 1 x transmitter 1 x conversion head 1 x charging cable Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.