SM18N3 Audio Details Technical Specifications Remote Speaker Microphone (IP54)IP54 compliant remote speaker microphone with emergency call button and 3.5mm external earpiece jack.Find a dealerHighlightsFunctionsTechnical SpecificationsMicrophone sensitivity -42dB ±2dB @1KHz, speaker sensitivity 90dB ±3dB @300Hz - 3KHz average, impedance 16Ω ±15% @1.5KHz, rated power 1W, maximum power 2W, operating temperature -30°C to +65°C