LCD Display, Electric Voltage Tester

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!

This review is for Klein Tools RT250 GFCI Outlet Tester with LCD Display, Electric Voltage Tester for Standard 3-Wire 120V Electrical Receptacles. This is the best outlet tester I have seen so far. I love the backlit readout and that it gives you the voltage information too. All the features, including the GFCI test, work flawlessly. I have never had a Klein tool that I have been unhappy with, and I find this tester to be a great value.

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.

Great tool or electrician or noncertified electrician who cares about doing their jobs the right way. The large back-lit LCD shows voltage, wiring condition, and more info including detects open neutral, open ground, and other common wiring errors

Works well

in the field i work i need a reliable circuit tester, this is one i recommend, i got another one for a co worker, since he liked the way mine worked, he is really enjoying it, if you work on electrical, get one it is well worth the price and the headaches it saves.

This outlet tester gives me a lot of peace of mind when working around the house. It’s simple to use—just plug it in, and the bright LCD display gives clear, easy-to-read results. The color-coded indicators and built-in GFCI test function make it incredibly functional for quickly checking outlets and ensuring wiring is safe. It’s also reassuring to know I’m catching potential issues before they become bigger problems. The build quality feels solid and durable, so I don’t worry about it failing when I need it most. It works well every time I’ve tested it, even compared to a more expensive professional tester. This is a perfect tool for homeowners or DIYers looking for something safe, accurate, and functional to check their electrical systems.

Klein tools are known for making great product and this one has great built quality. Very easy to use and great features for my needs. Love the memory and the LCD backlight feature. Definitely recommend getting one of these testers for your DIY around the house or jobsite.

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.

Buen producto muy util para probar los contactos.

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!

Cumple su funcion y es e un material duradero.

Amazing tool. Perfect for home-owners that are weary on the state of their outlets. Did a couple of outlet replacements and this unit came in handy to test and help identify faults. Even on GFCI outlets!