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) at 1?Bar 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. 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.