






⚡ Master your electrical domain with precision and confidence!
The Extech CB10 is a professional-grade AC circuit breaker finder and receptacle tester designed for both home and industrial use. Featuring two-pass calibration technology, it ensures 100% accurate breaker identification without shutting off power. Its integrated GFCI tester detects common wiring faults and tests safety outlets with dedicated LED indicators and a trip button. The device includes a manual sensitivity dial to eliminate false signals, comes with a 9V battery, and boasts a compact, ergonomic design for easy storage and immediate deployment.





| ASIN | B0014FNWJG |
| Best Sellers Rank | #224,461 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #303 in Circuit Testers |
| Brand | Extech |
| Brand Name | Extech |
| Color | Green, Red |
| Customer Reviews | 4.3 out of 5 stars 2,837 Reviews |
| Global Trade Identification Number | 00793950400104 |
| Included Components | CB10 |
| Item Dimensions | 10.1 x 5.4 x 1.5 inches |
| Item Height | 1.5 inches |
| Item Weight | 0.02 Kilograms |
| Item dimensions L x W x H | 10.1 x 5.4 x 1.5 inches |
| Manufacturer | Extech |
| Measurement Type | Voltmeter (for AC voltage) |
| Minimum Operating Voltage | 110 Volts (AC) |
| Model | 1218G94EA |
| Power Source | Battery Powered |
| Style | CB10 |
| Style Name | CB10 |
| UPC | 785533703542 793950400104 |
| Unit Count | 1.0 Count |
| Warranty Description | 1 Year |
D**D
Works through walls too
I just bought this to use in my older house and it has worked great for finding the breakers and even wires in the wall! I find for the walls it can be a little hard to trace as I feel like the wires have to be within 1-1.5" deep with the sensitivity maxed out and you can loose the signal being as little as 1/4" off from the trail, but it totally works and let me trace a few wonky paths so I could figure out exactly where the wire was moving in my walls and even to a buried junction box. I also really like the manual adjustment since it lets me hone in the breaker real quick and I don't have to scan the breaker like you see with the auto-adjusting ones. I just go to the breaker on about "half" sensitivity, move fast, and when I hear the beep I just drop it to lowest immediately and find it every time. Also due to the manual aspect of it, it let me figure out that a circuit was being served by 2 breakers and tracing which wire went where within the 14/3 wire sleeve itself since I could turn the sensitivity down so low. The socket tester works well too from the few tries. Only real issue I noticed is if you have any of the circuit based dimmers that basically everyone uses now since LED lights need them for dimming, it'll also send a signal in the line that this can pick up. It's real obvious though as it beeps much faster and sounds funny compared to how the device normally works, so either just ignore it and follow the normal beeps or turn off the light, surge protector, etc. Great device and wish I had one sooner to figure out all this weird wiring and no constant breaker switching either!
S**N
Works well and reliable
Very effective tool, I use it on almost every repair call. It made me look like a pro when I labeled all the sub panels for a commercial warehousing customer of mine who berths hundreds of food trucks boats and RV's. When they need to know where a breaker is in one of their 9 panels they can find it because they are all labeled now at the receptacles. It works for two and three leg circuits without neutral legs better than I thought it would. I used alligator clip jumper wires and pins to connect the plug to the various twist lock and range receptacles that the food trucks plug into for the night. It is a little hazardous to have open hot wires using alligator clips, but it works safely and well well with a little caution and a vigilant helper. I am very happy. I have also used it to locate GFI feeds and test GFCI receptacles. It is a good tool and a great price. It is not a hard core unit in the long run, but it is not crummy cheap either. I am a professional repair contractor and although I am not destructively hard, am very hard on my gear in normal use, electrical work is a rough discipline. I drop things a lot, and I use it up, burn it out, and play it as productive as possible. I have no problem with the fact that a saws-all lasts me about a year during rough in work. The tool makes its money several times over. The plug-in on the breaker locator broke when I was testing a GFCI. The ground prong came out of the plastic body. The prongs are good thick stainless steel but it needs a larger chamfer ring to hold it into the plastic, at least the ground prong anyways. I absent minded threw both the plug and receiver away immediately on the job site with some other debris and wire clippings. I looked closely at the body of the plug and hastily decided not to try to open it and fix it. I figured I would just buy another one. Now I wish I had saved it and looked closer later. I have a entry level quality toner kit also and love it. I have dropped it twice and opened it and fixed the antenna cartridge and the speaker twice. I can not see the point in spending over 100 bucks on instruments that are gonna get beat up, or stolen anyways. This is an excellent tool whether you are a home-owner or a professional. The seller gets it out quick and with good packaging. If I am more careful with the plug I am sure it will not break again.
L**G
Works very well, but you have to fiddle with it a little to get it dialed in.
I had no idea this kind of product existed until I was having trouble tracing circuits in my house. The house is midcentury, so not crazy old, but it has had some interesting wiring work done over the years. During those years nobody has apparently taken the time to accurately label the breaker boxes downstairs, so you can never tell what circuit anything is on. Normally this is frustrating, but not the end of the world, but recently was a much bigger problem. I got a MIG welder that I can use for hobby stuff, but it has to be on a 20AMP circuit instead of 15AMP. Normally this wouldn't be an issue, just double check it is on a 20AMP circuit and that the outlet is also rated 20AMP, but of course I couldn't tell which outlet was on which circuit. I didn't want to have to guess or start flipping breakers to see what turns off, so I looked online. I was originally just hoping for a test plug that could give me some sort of further information. I already have the ones that just tell you if the outlet is wired correctly. I was SO pumped when I found out this thing existed and wasn't crazy expensive. I couldn't wait for it to get here. I tried it out and I was able to quickly make sure the outlets, including GFI, were wired correctly (because the plug section also performs this function) and which circuit they were on. It saved so much time and messing around and gives me a great option for future situations that are similar. I have even already lent it to a couple of friends who didn't know this technology existed and were also very excited to make use of it. Using the tester can be a little delicate, but I did look at some other reviews that were helpful. Basically you start by plugging in the dongle to the outlet you want to find the breaker for, then you start sliding the handle along with the tip making contact along the center of each circuit breaker. Then you keep turning down the sensitivity until it only beeps on one breaker switch and that is the loop that the plug is attached to. When it gets the test signal from the plug, the handle frantically but rhythmically beeps. It takes a few tries to recognize it, but it is a distinct sound. The sensitivity adjustment has to happen every time you use it, as far as I can tell, but after the first time it is much easier because you know what to listen for.
W**M
This thing paid for itself the first day of use.
This sensor works so well once I learned how to adjust the sensitivity (about 3 or 4 minutes) . I was able to find what breakers controlled which rooms and lights easily. An easy one person job.
R**A
Superb tool for solving basic home wiring issues
This has helped me unravel the mysteries of my house wiring. You plug the transmitter end into an outlet (three prong) and go hunting for the right breaker with the sniffer. You can buy adapters to plug into light sockets and even alligator clips to attach the transmitter to bare wires if you are feeling bold. The tool has a sensitivity knob on the sniffer. This is the part that you get a feel for when using the tool. If you have the sensitivity too high, it's difficult to identify the exact right breaker within the breaker panel. The trick is to lower the sensitivity while you are sniffing until it only beeps when you hover over a single breaker. Bear in mind there is a proper orientation indicated on the end of the sniffer. Now I have one of these, I wouldn't be without it. It's really useful and as you get better with it, you can use it for tracing wires and all sorts of things to get you out of a bind. Highly recommended.
D**M
Reliable for a while, then died (bad power switch)
It worked well for nine years, until it didn't. I traced the problem down to the power switch, which is part of the sensitivity adjust knob. There's a metal arm that gets pushed away from a contact when the switch is "Off", and allowed to bear against the contact when "On". Now, when "On", the two seem to be touching, but aren't conducting electricity. Jumping the two with a screwdriver turns the unit on, but that's a PIA. I'll try some sandpaper to see if it'll fix it. Otherwise, a bit disappointing. Edit: sandpaper didn't work, as some of the switch's solder joints were bad. Fixed solder joints, and bridged switch so that the unit would be on every time I plugged in a battery. Worked, until I reassembled, when it again didn't. Threw it away. Yes, it's nine years old, but I used it perhaps a dozen times in that span, and that isn't a lot.
J**T
Easy to pinpoint the correct breaker.
Our panel labels are no longer accurate following a partial remodel a few years ago, and a service- and panel-upgrade last year. I need to replace an outlet without accidentally shutting down our computers, and the Extech 1218G94EA CB10 Circuit Breaker Finder made it easy to locate the right breaker without shutting anything off first. I've read the reviews of other breaker-finders and their users' difficulty pin-pointing the one correct breaker out of the several (or many) the tool identified. This tool has a sensitivity dial allowing you to manually decrease the sensitivity until it only responds to one breaker as you scan the panel. Since it does not try to adjust itself automatically, you get to tweak the sensitivity up and down until you're confident you've found the right breaker before you shut anythnig off. When you do shut off the breaker you identified, the signal disappears completely, even at full sensitivity, as a confirmation. When you go back to the outlet, the transmitter lights will be off as a second confirmation that the circuit is dead. This is a two-piece tool: A transmitter (which is also a wiring-fault tester and GFCI-protection tester) that you plug into the outlet whose breaker you need to identify; and a receiver/scanning tool that you pass over the breakers on your panel and which beeps and flashes when it finds the transmitter's signal. The transmitter comes with a cheap 9v battery which probably won't last long, and which will likely eventually leak and damage the tool. I'm using mine (hey, I had to try out my new toy!) but I'm going replace it with a high quality battery Alkaline battery very soon. I'd call this a home handyman-/handymaam-level tool for its less rugged construction than what a pro would need and expect, and it's priced to match. No stars off for that - it's the right tool for the market it serves. A pro tool would probably include adapters for a light socket and a set of jumper wires, which I didn't want or need right now. If and when I do, those are hardware store items.
P**.
Works Great !
In the past, the ability to find the correct circuit breaker for a set of outlets in my house was maddening. I had to use the "trial and error" method to find the right circuit. I decided to use technology to increase the speed and efficiency of the process. The product was highly rated so I decided to make a purchase. the product is of high quality and easy to use. You plug in the "transmitter" into the outlet and you use the receiver to find which circuit breaker is receiving the signal. You are able to adjust the sensitivity to narrow down the right breaker. It takes some iterations to find the right sensitivity, but once you have that dialed in, it makes easy work of finding the right circuit breaker. This is a must have if you are an electrician by trade.
Trustpilot
4 days ago
2 months ago