The WPS2900 Series is a mass notification system from Whelen Engineering Company, Inc., of Chester, Connecticut. The system first makes a warning tone to alert individuals of danger and follows with a clear voice message to explain the warning. One to 10 omnidirectional speakers are assembled in a vertical column and emit a choice of six warning tones. The public address system includes the capability to transmit live voice and prerecorded messages. The battery-powered units offer a minimum of 30 minutes of full power output. The system can be controlled locally or remotely. Options include solar power supply, noise canceling microphone, alternate tone set, and digital voice message capability.