Review on 🔌 Sperry Instruments GFI6302 GFCI Outlet Tester, Standard 120V AC Receptacle, 7 Visual Indication & Wiring Legend, for Home & Professional Use, Yellow & Black by Carl Durant

I thought I knew a lot about electricity (engineering university graduate). I make mistakes working with electricity at home. This small and inexpensive gadget is great. This has helped me detect any outlet that isn't plugged in properly. Before that, I check the outlets, including the ones I installed by plugging in a small lightbulb. If it is lit, the outlet is working. NOT RIGHT. This device detects outlet wiring problems even when the lightbulb turns on: 1) Neutral and hot swap (the one in my garage is like that, I fixed it) 2) Open ground on a new outlet I installed, even with the right wiring but the sockets are on the same line is ok. Find out that this outlet is defective, replace it with a working one and the problem will go away/. 3) GFCI Compliance Test: This gadget is hard to live without. and much more. I've noticed that the "open terrain indicator" is very confusing: only the middle YELLOW light should be lit. Mine also shows some RED and a half lit YELLOW on the right! This can be confused with "RIGHT". I have to buy another brand to try. Due to this issue, the rating has been reduced from 5 to 3 stars.