1.Designed in accordance to ISO and IEC914.2.Speaking and listening function.3.The system power supply for all the delegate units is provided by the main unitat 24 safe voltage.4.9P-DIN plugs for system T-type connection.5.Unidrectional electrets MIC and HIFI voice loud-speaker6.Electric capacity type microphone, equipped with windshield cover. 7.Extended pipe optional.8.The annular red indicator lamp could show the state of the microphone.9.The microphone has a speaking button and indicator lamp; it can control the stateof speech.10.Equipped with an earphone output jack ad REC output jack.11.Auto-off function: The microphone would close automatically in 30 seconds aftermaking a speech.12.The chairman unit number in the system is unrestricted, can join in any positionof the system.13.Chairman unit equipped with an earphone output jack and wireless MIC input jack14.Chairman unit can turn down delegate MIC by press the priority button.15.Indicative sound for chairman unit (optional)16.Sensitivity:-44dB?dB17.Frequency response:40Hz-16KHz18.N.W.: 0.9kg 19.Installation: Embedded20.Dimensions: 230x110x65mm/ MIC pipe 390mm producing area:China payment:T/T in advance, L/C at sight supplying capacity:2000pcs/month