Details Allows a standard 2.5mm cell phone headset For use with DX Series BP200, BP210 and BP300 beltpacks Item Code Catalog No. CZ11453 Technical Specifications Frequency Response: 200 to 3.5kHz Earpiece Impedance: 32Ω or Greater Microphone (Electret): 1500 to 1800Ω 1.5v Bias Earpiece Insertion Loss: 1dB Typical Operating Temperature: -4°F to 131°F (-20°C to 55°C) Connector: 2.5mm Pl