This 2-Piece Klein Tools Digital Circuit Breaker Finder with GFCI Outlet Tester and Circuit Breaker Finder Accessory tool kit does more than just indicate standard circuits. Adapters in this kit indicate the correct breaker of bare wires or other exposed conductors. The Transmitter is connected to the electrical outlet or fixture in the circuit while the receiver is used to scan the breakers in the circuit panel. The Transmitter also features a GFCI outlet tester. For more than 160 years, Klein Tools has manufactured premium-quality, professional-grade hand tools that deliver the performance, durability and precision needed to get the job done right. Our family of engineers, workers and craftsman continue to put six generations of expertise into every tool we create by using only the highest quality materials, superior workmanship, and keeping manufacturing as close to home as we can. Klein isn't just the name of our company, it's also our family name. And since we're an American company that's family-owned and family-run, you know you can count on us to be here tomorrow. Klein Tools doesn't just make great products, we make great products that stand up to the demands of the professionals who use them every day ... Since 1857. ACCURATE CIRCUIT IDENTIFICATION Circuit Breaker Tool Kit helps locate the correct circuit breaker for electrical outlets or fixtures, saving time and effort CLEAR VISUAL AND AUDIBLE INDICATIONS Digital Circuit Breaker Finder with GFCI Outlet Tester Cat. No. ET310 receiver provides clear indications when the correct breaker is found VERSATILE OPERATION Works on 90120V AC circuits, suitable for various residential and commercial applications GFCI OUTLET TESTING Transmitter features a builtin GFCI outlet tester to inspect wiring conditions and test GFCI devices ADDITIONAL ACCESSORIES Circuit Breaker Finder Accessory Kit Cat. No. 69411 includes a 3prong to 2prong grounding adapter for enhanced compatibility LIGHT SOCKET ADAPTER Light socket adapter allows for easy circuit identification in lighting fixtures ALLIGATOR CLIP ADAPTER Alligator clip adapter enables the tools use on bare wires, expanding its versatility