The transmitter possesses the very tender microphone and the low level of own hums. To work in ranges 88 maybe-108 MHz and also 140-150 MHz. The power supply since 3 to 12 of V ( the battery or DC) Dimensions 25x10x5 mm Range 150-200 m The temperature of work from -20 to + 50 st. the C Power from 2 to 10 mW ( it depends from tension power supply) The time of work from 4 till 4300 hours ( it depends from applied battery)