The Fluke BK120 SmartTrace Circuit Breaker Finder is a tool for identifying circuit breakers in electrical panels and detecting voltage with NCV mode. It is an essential device for electricians, homeowners, and maintenance professionals, to simplify electrical work, circuit tracing, and troubleshooting. The product includes a receiver that acts as the switch finder and non-contact voltage detector, and a transmitter that tracks the receiver and also acts as a socket tester.