AR Timer
The AR Timer was a signal timer produced by Federal Signal Corperation. It is capable of two three-minute signals, attack and alert. There was also a unit called the AR-5 that increased the signal duration to five minutes. In addition to the Alert, Attack, and Cancel buttons on the unit itself, the timer provides terminals for either external push buttons or remote activation equipment. In remote installations the AR Timer was generally installed inside of an ARCH cabinet, which contained the timer unit as well as remote activation equipment, such as a radio with tone decoder.