Klein Tools RT250 GFCI Outlet Tester with LCD Display, Electric Voltage Tester for Standard 3-Wire 120V Electrical Receptacles

I picked up the Klein Tools RT250 GFCI Outlet Tester to help check a few outlets around my house, and I’m honestly impressed. This thing is super straightforward, just plug it in, the lights pop on, and you instantly know what’s going on with the wiring. No guesswork, no complicated setup, just clear results. The display is bright and easy to read, and the built-in GFCI test button is a lifesaver when checking bathroom and kitchen outlets. It helped me identify a miswired outlet in an older part of my house that I never would’ve caught otherwise. For something at this price, it feels durable and professional like something an electrician would actually use. If you’re a homeowner, DIYer, or just want peace of mind about the electrical safety in your place, this is a solid buy. Fast, accurate, and super easy to use. Highly recommend!

As an electrician or serious DIY-er who cares about doing things right, this tester has quickly become one of my favorite go-to tools. The RT250 is packed with features and built to handle real-world job-site demands. What stands out: The large back-lit LCD display clearly shows voltage, wiring condition, and the time it takes a GFCI to trip—making testing thorough and faster. It automatically detects open neutral, open ground, and other common wiring faults—no more guesswork. The built-in GFCI test button trips the device and the timer measures how long it takes—great for verifying that the GFCI meets spec. Rugged build: rated for a 6.6-foot (2 m) drop and meets CAT II 135 V safety rating—solid for a busy job site. It’s compact and lightweight (just 4.8 oz) but feels tough—durable housing and robust plug make it practical for everyday use. My experience on the job: I’ve used this tester across new installs, upgrades, and troubleshooting older receptacles. It quickly flags incorrect wiring (open ground, reverse hot/neutral, etc.), and the extra info like voltage readout and trip time saves me from coming back later for retests. Switching between circuits is fast, the screen holds readings with Auto-Hold (perfect for hard-to-reach outlets), and the indicator LEDs still give quick visual cues when I want them. Final verdict: If you’re working with North American 3-wire 120 V outlets (especially ones with GFCI protection), this tester hits all the right notes: precision diagnostics, rugged build, and efficient troubleshooting. It’s built like a pro tool—and priced so that it’s worth having in your bag every day. I highly recommend it.

I have one of those 3 LED testers already, the ones with the 2 yellow and one red light... and has a legend on it so that you can tell what is what. Works great... only issue is that when I was working outdoors or in a brightly lit room, it wasn't so obvious which LED were lit. So I bought the Klein as it wasn't a bad price and had the built in GFCI too. My old set, I had a separate GFCI tester which also worked great but just meant I had 2 separate testers. I played with the Klein soon as I got it having installed the batteries (Klein supplied I might add!!!!). You need to hold the power button down a couple of seconds and then the LCD comes alive. I tried it in various outlets around the house and found it to be a really effective device. The unit has only 2 LED's and there's no mistaking when they light up, both bright... A green one which clearly means OK and a red one meaning a fault in the wiring has been detected. I already had a purpose made miswired test lead I used for verifying the fault detection capability. Works great. I also like that it provides a reading of the actual voltage detected. It's not just a passive device. I have only one minor concern... When I put this in my toolbox I'm worried about something resting on the power switch and running the batteries down, so for now, having already carefully cut around the edge of the packaging, I'm keeping it in the packaged plastic. Might be overkill and maybe I'll buy a protective case for it if I feel inclined but for now, perfectly happy with the device and definitely recommend over the typical passive receptacle testers, even though they may be half the price.

This Klein Tools RT250 Outlet Tester is a significant step up from the basic three-light testers. The LCD display is bright and easy to read, giving you actual voltage numbers and clear text for any wiring faults. It takes all the guesswork out of troubleshooting, and the GFCI trip testing function works perfectly every time. It’s a rugged, well-built tool that feels like it will last for years. Highly recommend it for both professionals and home DIYers!

Works well

An excellent product that takes the guess work out of electrical outlet installation. The display is easy to read and lets you know definitively if you are wired correctly or not. The red and green lights are nice as well as the LED voltage readout. Very accurate and a good value. Also great for checking GFI circuits.

This is a great tool for testing a GFCI if you are having problems with one in your home. I found out that mine was bad using this tester.

The essentials. Hot Neutral and ground for your 1800 watss of 120 VAC coming out of the wall. A most practical tool that in an instant lets you know the status of your outlet. When I don't have a Multimeter handy, this covers the tests perfectly. I work in a place that has questionable power from time to time. Something you should never be in doubt. This device helps you know your AC power is working correctly. An indispensable tool to keep you safe and aware of live outlets. A must have.

Probador muy bueno y excelente y exacto buena marca se los recomiendo muy bien como herramienta los vá a sacar de apuros.

Does exactly what the advertising says. Seems really well made from solid material.

Calidad y exactitud

This tester could save your life. Used in an RV with no issues - the tester showed all was well. Using the same tester in a house, it gave an indication of potential wiring issue, as the voltage showed 30VAC on first check and 123V on a subsequent check. It will also indicate ground issue, reverse polarity. Glad to have bought.

This product is great! Backlit screen is very easy to read, the bright red and green indicators mean you know what’s happening even if you don’t have perfect line of sight to the screen, and the memory hood function means you can still see all the information after removing the device from the socket!! Not 100% sure on the accuracy of the meter but so far it seems to be pretty good!