The BESANTEK BST-CBF02 Circuit Breaker Finder with GFCI automatically indicates the right breaker; and with the help of the GFCI tester, it can also verify if wiring is correctly wired. If the wiring isn't correctly wired, the BST-CBF02 will indicate which of the five fault conditions exists in the system. The tester is suitable for house, office, factory power network reconstruction, and more applications.