

🔧 Master your circuits like a pro—no more breaker hunt blues!
The Klein Tools ET310 is a professional-grade AC circuit breaker finder featuring a two-part transmitter and receiver system that accurately identifies breakers on 90-120V circuits. It includes an integrated GFCI outlet tester for comprehensive wiring safety checks. Compact and battery-powered, this tool offers clear visual and audible signals for quick, hassle-free electrical troubleshooting, trusted by professionals for over 160 years.












| ASIN | B07QNMCVWP |
| Best Sellers Rank | #1,841 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #3 in Circuit Testers |
| Brand | KLEIN TOOLS |
| Brand Name | KLEIN TOOLS |
| Color | Orange |
| Customer Reviews | 4.7 out of 5 stars 25,056 Reviews |
| Global Trade Identification Number | 00092644692406 |
| Included Components | Includes Transmitter, Receiver, user manual, and 9V battery for Receiver |
| Item Dimensions | 10.96 x 2.16 x 1.39 inches |
| Item Type Name | Klein Tools ET310 AC Circuit Breaker Finder with Integrated GFCI Outlet Tester |
| Item Weight | 7.2 Ounces |
| Item dimensions L x W x H | 10.96 x 2.16 x 1.39 inches |
| Manufacturer | Klein Tools |
| Maximum Operating Voltage | 120 Volts |
| Measurement Type | Voltmeter and Ohmmeter |
| Minimum Operating Voltage | 90 Volts |
| Model | ET310 |
| Power Source | Battery Powered |
| Style | Circuit Breaker Finder |
| Style Name | Circuit Breaker Finder |
| UPC | 092644692406 |
| Unit Count | 1.0 Count |
| 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.
L**X
Effective tool
Works well for mapping and testing outlets on the circuit breaker board.
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.
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.
F**S
Great electrical tools
Klein tools work very well for home repairs. Have used these tools several times and have saved money on simple electrical repairs
K**R
A must-have for unlabeled breaker panels!
Our builder left the breaker panel completely unlabeled, making simple repairs a nightmare. This Klein Tools ET310 worked perfectly to map out the whole house. The receiver is very accurate—it might beep on a few breakers during the first pass, but once it "learns" the panel on the second pass, it points directly to the right one every time. It saved me hours of running up and down the stairs or yelling across the house "Did that turn it off?"
T**E
works well...
works well..good product .
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.
Trustpilot
2 weeks ago
1 week ago