Monitor Range 10-35sq.m,suit for prison,jail room,any small room, ssmoke detector ... Over-loading protection, Lightning proofAudio Preamp Build-inOutput Connector Power+, Audio and GND Cable 3 x 0.5mm2 RVVP cableVoltage DC ... Material PVCSize 60mm × 22mmWeight 30gStandard CE FCCDetail Introduction:*Professional wired audio surveillance & monitoring microphone.*Low noise, Low echo, clear speech, low ...