

⚡ Breakers found. Safety tested. Job done smarter.
The Klein Tools ET310 is a professional-grade circuit breaker finder with a two-part transmitter and receiver system that quickly and accurately identifies breakers on 90-120V AC circuits. It features integrated GFCI outlet testing, clear visual and audible signals, compact storage design, and trusted Klein durability—perfect for electricians and savvy DIYers who demand precision and efficiency.












| ASIN | B07QNMCVWP |
| Batteries | 1 9V batteries required. (included) |
| Best Sellers Rank | #877 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #1 in Circuit Testers |
| Brand | KLEIN TOOLS |
| Color | Orange |
| Date First Available | April 15, 2019 |
| Department | Unisex-Adult |
| Global Trade Identification Number | 00092644692406 |
| Item Weight | 7.2 ounces |
| Item dimensions L x W x H | 10.96 x 2.16 x 1.39 inches |
| Item model number | ET310 |
| Manufacturer | Klein Tools |
| Maximum Operating Voltage | 120 Volts |
| Measurement Type | Voltmeter and Ohmmeter |
| Min. Operating Voltage | 90 Volts |
| Power Source | Battery Powered |
| Product Dimensions | 10.96 x 2.16 x 1.39 inches |
| Style | Circuit Breaker Finder |
| UPC | 092644692406 |
| Upper Temperature Rating | 60 Degrees Celsius |
M**C
Trusted Klein Tools Brand, Easy To Use
I started using circuit breaker finders about ten years ago. I was very happy to discover that there was such a thing. At the time, I bought the cheapest one I could find. It worked Ok, but still required some trial and error to find the circuit I needed to turn off. When I saw that Klein Tools made a circuit breaker finder, I thought I'd try it because I've always been impressed with the quality of Klein electrical tools. My neighbor is a Master Electrician and he uses many Klein brand tools. Compared to my old, cheap device, the Klein Tools instrument has better sensitivity and accuracy. The visual notification is plenty bright for dark rooms where the panel box can be found. This unit allows me to quickly and easily locate circuit breakers. I don't always find them on the first try, but it sure beats pure trial and error. I already had a cheap dedicated voltage tester, but the transmitter with this Klein set also detects voltage and proper wiring of outlets! Best of all, this set fit perfectly into the hard case I already had. Also, Amazon sells good hard cases that will fit this device well.
J**Y
Simple, Solid, and Well-Priced Breaker Finder
The ET310 looks compact and clean, easy to spot in my tool bag. Features are exactly what I need: it finds the right breaker quickly, and the built-in GFCI outlet tester means I don’t need a second tool. Build quality feels solid—nothing flimsy—and it worked reliably on the first try. It’s very simple to use, even if you’re not a pro; the lights and tone make it clear when you’ve got the right breaker. For the price, it’s a great value and an easy recommendation for homeowners and DIY jobs.
B**N
Accurate
Hands down one of the most useful tools I own. Finds circuits fast and accurately, even in tricky setups. Saves a ton of time on the job. Highly recommend for electricians. Solid and great quality.
P**P
Works well.
I spent almost an hour trying to decipher the scrawl on the label in the breaker box to determine which might be the one to the socket that I wanted to replace. Almost all of them said: sockets/lights Thanks. So much ... I then spent half an hour flipping off likely candidates. Nope. Came to Amazon and spent some time trying to decide between this Klein device or the similar Fluke one. This seemed to have a lower proportion of bad reviews, and I do have other Klein tools which I am relatively happy with. Ordered it for same day delivery. Of course, it was "end of day" delivery, but still ... plugged in the transmitter and had the breaker located five minutes later. Next morning I swapped the faulty socket. I verified the power was off with the included voltage detector, after testing it against several sockets and light switches to be sure it worked ok. The only reason I have knocked off one star from an otherise five star review if for the cheap and nasty plastic these are made of. Plastic is ok, but this is the sort of plastic you associate with free gifts in packets of cornflakes. And these were anything but cheap.
R**K
Good AC Circuit Breaker Finder
Works as advertised. Very handy for determing what circuit breaker is connected to your outlets. High quality product. The case is also nice.
J**I
Excellent Tracking Fuse Tool
Works extremely well for tracing down the fuse to the room. Easy to set up and straight forward function. The voltage appears to work with any standard home panel but I had a few instances where I got a few false alarms. The unit requires running up and down all the fuses twice to pin point an exact near identical signal match. I would say it is durable and the design is modern. Can fit in any work bag or pocket.
K**R
practical - perfect for the handy-man!
GREAT VALUE! it is being added to my boyfriends tool bag for work. He's a home inspector and this allows him to offer additional services to clients and replaces some of the items he already has. Super happy about the quality, features and size!
M**.
Klein circuit locator
I bought one for myself and two others for gifts, works great, makes finding the correct circuit a breeze if your breakers aren't labeled or labeled correctly, it is very easy to use, make sure to follow all safety precautions when working with electricity
A**.
هذا لاينفع لنظام الكهرباء ٢٢٠ فولت
J**N
Awesome
F**B
Ce détecteur de disjoncteur est un outil extrêmement pratique qui fait gagner un temps précieux lors de travaux électriques. Il permet de localiser rapidement et avec précision le disjoncteur correspondant à une prise électrique ou à un luminaire, sans avoir à couper les circuits un à un. Le système est composé de deux parties bien pensées : un émetteur qui se branche directement sur la prise ou le luminaire à identifier, et un récepteur qui sert à balayer le panneau électrique. Dès que le bon disjoncteur est trouvé, le récepteur émet des signaux visuels et sonores clairs, ce qui élimine toute confusion. Compatible avec les circuits de 90 à 120 V CA, l’émetteur intègre également un testeur de prise GFCI. Cela permet de vérifier l’état du câblage de la prise et de tester le bon fonctionnement des dispositifs GFCI, un vrai plus pour la sécurité. La prise à trois broches est parfaitement adaptée aux standards nord-américains. Autre point appréciable : l’émetteur se range directement dans le récepteur, ce qui rend l’ensemble compact et facile à transporter ou à ranger dans une boîte à outils. Un excellent outil, autant pour les bricoleurs que pour les professionnels, simple à utiliser, précis et très efficace. Un indispensable pour toute intervention sur un panneau électrique.
J**N
Magnifique
B**R
Curious from the negative reviews, I thought as an electrical engineer, I would get it to work. Well, scanning the breaker board on second pass, it showed the wrong breaker. The microwave which is the only device on that circuit. The tester was plugged in another outlet. So I switched the breaker off, it still showed that breaker. Reset the scanner, learned the board all over, same wrong circuit. Or rather the middle of the breaker board. Then I read in the manual to unplug all devices from the circuit being tested. If I need to do that, this tester saves no time. Fortunately, some reviewers shared how they got it to work. Remove the breaker board cover and scan the wires. Bingo! Found the circuit the gas boiler is on. Without the need to unplug and reset the clocks in each room controller. 4 stars after all.
Trustpilot
2 weeks ago
2 weeks ago