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. Introduced in 1918, Model A is still used today in many rugged and extreme environments and applications.

The fractional horsepower motor on Model A 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.