... at same time 2, Infrared manual frequency adjustment HT-8112L Wireless MicrophoneFeatures:1, Number of channels: 200 CH, Max available for ... pcs devices use at same time2, PLL (phase-lock loop) technology, frequency stability∠±100Hz3, Infrared manual frequency adjustment4, Two channel R ... distance: 100 ~150 meters, depends on environmental conditions HT-8112L Wireless Microphone