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. Introduced in 1918, the model A is still used today in many rugged and extreme environments and applications. The model A features a universal motor and operates with 120 VAC or 125 VDC. The fractional horsepower motor drives a ported aluminium 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 or five minutes off. This siren produces an attention-getting 103 dBA at 10 ft and 1060 Hz at full RPM. The model As 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.