Head-mounted Microphone, Headworn Microphone with Screw Lock Beige High Sound Quality for Lectures Broadcast Rooms, Commentaries, Guides, Interviews, Etc Specification: Item Type: Head-mounted Microphone Material: Vacuum Tube Color: Beige Current: Less than or equal to 0.5mA Signal to Noise Ratio: Greater than or equal to 56dB Weight: Approx.23g/0.8oz Monomer: Back Electret Type Directivity: Unidirectional Single Directivity Frequency Range: 50Hz-16KHz Sensitivity: -39dB?1dB/?0dB=1V/Pa at 1KHz? Output Impedance: 680 Ohm ?30%(at 1kHz) Working Voltage: DC 1.0V-10V Standard Power Supply: DC 1.5 V Package List: 1 x Microphone 1 x Fixed Buckle