... meeting room, visitation room,classroom Flat Style Microphone,Omni Directional, Monitor Range 10-40sq.m,Size 95mm*95mm*30mm, Weight 80g ... cableVoltage DC 12V (8 ~ 20V) Current 20 mATemperature -25°C ~ 70°CColor Sky-blueShell's Material PVCSize 95mm × 95mm× ... etc.*Excellent voice experience, widely working temperature: -25~75°C*According with CE,FCC standard. C.TRADIO audio surveillance microphone