Master your jobs with speed and accuracy with the Greenlee GFCI Circuit Tester (catalog number GT-10GFI). Designed for plumbing experts, this circuit tester polarity cube makes it quick and easy to troubleshoot 20 VAC grounded outlets and test GFCI receptacles to identify any wiring faults. It's a reliable tool to help you ensure your outlets are grounded and wired correctly and is made for use with 3-wire receptacles. With user-friendly features, the tester has 7 easy-to-read LED light indicators to allow for easy identification of the state of the socket for a convenient way to determine if the wiring is correct or incorrect. The compact and lightweight design offers convenient transportation and makes it easy to carry with you on the job and store when not in use. Constructed from durable, rugged materials, this circuit tester withstands years of heavy-duty use on the jobsite for a long tool life. Greenlee: Professional. Nothing Less.™