These ELECTRIC LOCOMOTIVE SOUND SYSTEM's were designed for the model railroader utilizing magnetic trips of the Horn and Bell. Each activation of the Horn triggers a different prototypical play pattern of Horn. The Bell activates by tripping the Bell to play, the second trip will signal the Bell to turn off. Horn triggers can occur during Bell triggers as well. This system can operate from track power and/or battery power. Put our authentic electric sounds into your locomotive! Now you can hear PRR GG-1 #4877 as actually recorded while in service! Actual sounds of the Cooling Blowers, Horn, Bell, and Brake Release. Pull the mighty GG1 out and hear the brakes release followed by the Cooling Blowers whining up to full rpm.