The Astatic 210 is a miniature-boundary microphone designed for installation in security, ambient monitoring and observation applications. The output level is variable from -50dBv (3.2mV) to -10.5dBV(300mV) @ 1ÂµBar which is designed to interface with security cameras, digital video recorders and other observation and recording devices. Astatic's internal audio limiter circuitry tames high sound pressure levels and improves intelligibility by protecting the audio signal from distorting sensitive recording circuitry in cameras and digital recorders. The integrated volume control is located on the side of the microphone and is protected from tampering when the microphone is installed. The integrated 150Hz, 6dB/oct high-pass filter attenuates unwanted low frequency energy. 8 to18 VDC (70mA) is required to power the microphone (not supplied). The connection is made through a removable 3.5mm terminal block plug connector on the opposite end of the microphone. The connector accepts DC power and outputs an unbalanced, amplified signal. The Astatic 210 housing is all-metal, designed for commercial applications. The threaded housing makes for easy installation into ceilings, walls, tables and other surfaces. Rubber isolation bushings and metal nut/washer hardware are also provided. Specifications: Operating Principle: Condenser Polar Pattern: Omnidirectional Frequency Response: 120Hz -18KHz Sensitivity: Adjustable, -50dBV (3.2mV) to -10.5dBV (300mV) @1Ã¦Bar Impedance: 50 ohms Maximum SPL: 100dB Self Noise: 22dBA Power Requirements: 8 to 18VDC, 70mA Connector: 3.5 mm terminal block plug with 180 degree wire-to-plug orientation, accepting 30 to 14AWG size wire. Polarity: Positive pressure on diaphragm corresponds to positive voltage on pin 2. Finish: Durable matte-white urethane Net Weight [Mass]: 2.4oz [.07Kg] Packaged Weight [Mass]: 5.4oz [.15Kg] RF Immunity: Meets or exceeds EN55103-2, E1, E2, E3 and E4 RoHS Compliant Specifications subject to change without notice. Included Accessories: 2 rubber bushings, hex nut and washer.