Now there is an economical tester to verify and trace circuits that requires only one person to operate. The Breaker Blaster is an amazing easy-to-use device that does two things. First, it verifies that a circuit is live by plugging the unit into a 120 VAC receptacle. A loud audible tone sounds if the circuit is active. Next, go to the breaker box and trip the breakers until the tone stops. The unique tonal pitch is designed to penetrate walls and can be heard at the box even from a great distance. The circular design fits nicely into a tool belt.