SM18A4 Audio Details Technical Specifications Remote Speaker Microphone (designed for connection to Car Kit)Intelligently designed remote speaker microphone with easily accessible PTT and emergency button, protected against accidental actuation.Find a dealerHighlightsFunctionsTechnical SpecificationsMicrophone sensitivity -42dB ±3dB @1KHz, PTT cycles ≥100000, speaker sensitivity 78dB ±4dB @1KHz, impedance 16Ω ±15% @1KHz, operating temperature -30°C to +70°CRelated Products PD702i UL913 Z1p PD702i X1ei