The Federal Signal Model A is a general-purpose electro-mechanical siren that produces a distinctive sound and tonal quality for industrial applications. It has a high maximum pitch which provides excellent contrast to industrial ambient noise. The Model A features a universal motor and operates with 120VAC or 125VDC. The fractional horsepower motor drives a ported aluminum rotor within the specially designed stator to produce a unique sound. A small internal fan cools the motor during operation. The recommended duty cycle is five minutes on/five minutes off. The Model A's metal housing is sealed with red powder coat for an attractive appearance and superior corrosion-resistance. The swivel mount bracket accommodates wall and surface mount installations.