... on desk all right Pinhole Style Microphone,Omni Directional, Monitor Range 10-30sq.m,Size 60mm*22mm, Weight 30g, ... Built in digital audio disposal circuit , two step dynamic de-noise disposal.*Special closed circle circuit design, eliminating electronic noise.*High ... experience, widely working temperature: -25~75°C*According with CE standard.Parameter:Monitoring Range 10~35sq.mtransmiting distance( ...