V - 7000 - a/B work high-definition LCD microphone on/off state and dynamic level and volume control 8 seconds automatically screen, electronic switch control volume microphone built-in single-chip microcomputer control circuit USES the long life, no noise light touch switch high temperature paint technology, sound good reducibility, high resolution, low noise, high efficiency of the noise suppression function, automatic tracking, chairman of the unit, voice switch priority, chairman of the unit.