The Circuit IQ digital plug tester pairs nicely with power mapping. To identify more than you had before, plug the tester in while you're mapping to verify outlet wiring with the easy-to-read screen. The two-inch screen displays more info than your standard tester, including easy-to-read, correct or incorrect wiring to the plug. Voltage readings between your line and neutral and line-to-ground wires. A non-contact tester to use in a pinch to check if a loose wire is live. Take your power mapping further with the digital plug tester.