Klein Tools RT390 - https://geni.us/uS7AA Meet the Klein RT390, a smart circuit analyzer that goes far beyond your typical outlet tester. In this video, I break down its most useful features — from GFCI and AFCI trip time measurements to load testing at 12A, 15A, and 20A, and even identifying voltage drops caused by poor connections. The RT390 gives you trip current (mA) and trip time (ms) so you can verify your GFCI performance meets code. It also color-codes losses over 5% in red, helping you