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KLEIN TOOLS

Klein Tools ET110 CO Meter, Carbon Monoxide Tester and Detector with Exposure Limit Alarm, 4 x AAA Batteries and Carry Pouch Included

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Availability: In Stock.
Fulfilled by Amazon
Arrives Monday, Sep 21
Order within 19 hours and 4 minutes
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Features

  • ACCURATE CO GAS MEASUREMENT: Detect and measure carbon monoxide gas levels with precision using our easy-to-use CO meter
  • PORTABLE AND PROTECTIVE: Carry our CO detector anywhere for user safety, with a built-in short-term exposure limit (STEL) alarm
  • DUAL ALARM SYSTEM: Stay informed about CO levels with both low (35 ppm) and high (200 ppm) level alarms, ensuring prompt action
  • AUDIBLE AND VISUAL ALERTS: Receive immediate warnings through audible and visual alarms, providing increased safety and peace of mind
  • CLEAR DISPLAY: Backlit display shows CO measurements (0 to 1000 ppm) and temperature (Fahrenheit and Celsius) for easy reading
  • BATTERY SAVING FEATURE: Auto-power off after 20 minutes of inactivity helps conserve battery life, extending the device's usability
  • CONVENIENT PACKAGE: Includes a carrying pouch and 4xAAA batteries, making it easy to transport and operate the CO meter efficiently

Description

The ET110 CO Detector is an easy-to-use meter that detects and measures concentration levels of carbon monoxide (ppm) and temperature (Fahrenheit/Celsius), making it the perfect choice for HVAC professionals. Features backlit LCD screen, warning indicator light, audible and visual alarms and multiple function buttons. Includes carrying pouch and 4 x AAA batteries. For more than 160 years, Klein Tools has manufactured premium- quality, professional-grade hand tools that deliver the performance, durability and precision needed to get the job done right. Our family of engineers, workers and craftsman continue to put six generations of expertise into every tool we create by using only the highest quality materials, superior workmanship, and keeping manufacturing as close to home as we can. Klein isn't just the name of our company, it's also our family name. And since we're an American company that's family-owned and family-run, you know you can count on us to be here tomorrow. Klein Tools doesn't just make great products, we make great products that stand up to the demands of the professionals who use them every day ... Since 1857.

Brand: KLEIN TOOLS


Style: Meter


Power Source: Battery Powered


Color: Orange


Product Dimensions: 7.74"D x 2.16"W x 1.46"H


Item Weight: 5.1 ounces


Alarm: Visual


Global Trade Identification Number: 55


Material: Blend


Unit Count: 1 Count


Brand: KLEIN TOOLS


Model Number: ET110


Global Trade Identification Number: 55


Manufacturer Warranty Description: Call vendor for warranty


Unit Count: 1 Count


Number of Items: 1


Manufacturer: Klein Tools


UPC: 092644690655


Built-In Media: Batteries, Pouch


Item Type Name: Carbon Monoxide Detector


Mfr Part Number: ET110


Power Source: Battery Powered


Alarm: Visual


Product Style: Meter


Color: Orange


Item Dimensions D x W x H: 7.74"D x 2.16"W x 1.46"H


Item Weight: 5.1 ounces


Enclosure Material: Blend


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, Sep 21

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Similar Products

Top Amazon Reviews

    • Works as is should! Must have if all appliances are gas.
Style: Meter
I bought three ten year life span Kiddie CO detectors to replace our alarms and a few months later, one was continuously tripping. Ordered this CO meter to find the source and no leaks, just a bad CO alarm. I held this Klein meter in front of the furnace exhaust outside the house and it immediately set an alarm. Works great and peace of mind knowing your family is safe if a $30-$40 alarm is going off! ... show more
Reviewed in the United States on March 28, 2026 by jnormn
    • Appears to Work
Style: Meter
Bought it for peace of mind, to check bedroom wood stove and vent joints for carbon monoxide leaks. Have not found any CO with it, or with a different brand whole room CO detector.
Reviewed in the United States on March 5, 2026 by Mountain Man
    • Great product
Style: Meter
This meter allows you to detect levels below what your CO2 detector measures. A great tool to protect your health.
Reviewed in the United States on July 15, 2026 by Sgurgola
    • Appears to be Worth Buying
Style: Meter
Was a little reluctant in buying this product because of some reviews in different sites, mixed reviews. I tried it about a foot away from the exhaust pipe of a vehicle and did get reading of 1 ppm and 5 ppm about three inches away which thought was way too low. I have a wall furnace so decided to put the sensor portion into the top vent with just the pilot light on. After about ten seconds got a consistent reading of 3 ppm, pulled it out and meter zeroed out. Tried it again and after a bit got a constant reading of 5 ppm so I felt the meter was functioning as it was meant to. Probably works better than other detectors under $100. ... show more
Reviewed in the United States on January 5, 2026 by JAMES PEDRAZA
    • Sensitive, easy to use, CO2 tester
Style: Meter
I had several propane leaks in a new house that we moved into. I bought the gas sniffer from Klein which was great. At that point I wanted to make sure nothing else was wrong. So I bought this. To test it I tried it in another house that had a ventless propane fireplace. Once i turned the fireplace on it registered a slight increase in CO2, but well within an acceptable range. It brought peace of mind to my wife which makes it priceless! ... show more
Reviewed in the United States on May 11, 2025 by Marnie Gordon
    • good thing to have
Style: Meter
we had our AC/heater unit inspected, they guy turned on the furnace and measured carbon monoxide with his unit and claimed he read 13ppm, and already sent us a quote for 15k to change the furnace to a new one. We were a bit shocked of course. We decided to double-check it ourselves and got this unit. We got it and, first of all, I wanted to make sure that it actually can detect carbon monoxide. We made sure to follow the instructions and we even turned and unit on and did the self-calibration (set button) outside, to make sure that it is calibrated in a space without any carbon monoxide. To get a positive control I lit a candle and blew it out. That first moment after a candle is blow out and you see a smoke, there is definitely some carbon monoxide forms. And, indeed, the unit went off. Showed something like 150 ppm (I put the meter right where the smoke from the candle was). In the rooms the reading was just zero. I was repeating these measurements in the rooms to make sure it is still zero, and it was. One time when I was messing around with it, I decided to breath on it just for fun, and it measured 3 ppm of carbon monoxide. I didn't know whether human breath supposed to have any, so I googled it and I saw that human breath for non-smoker should have 1 - 6ppm carbon monoxide. That was a cool observation, because it meant that the unit is indeed sensitive. So, since it so far looks that the unit is capable of measuring high (candle) and low(breath) amounts of carbon monoxide, and it still shows 0 ppm in our rooms, I think we won't be spending 15k for new furnace for now. ... show more
Reviewed in the United States on October 1, 2022 by Natalia
    • great tool, alerts us of CO before the alarm can go off!
Style: Meter
I bought this because we have had 2 CO alarms go off at like 10PM, which is no fun. Yup fire dept and local natural gas tech had to show and clear our house of CO leaks, BEFORE we could get back in our house. Turns out our gas fireplace had glass chips in it - something great new idea apparently - but they we covering up the air slots in the interior of the gas fireplace. So the CO was being kept down inside the fireplace, instead of pulling in the fresh air from the house. Once I removed the glass chips it did fix the problem!!! But I wanted to be sure and not get the opportunity to be stuck outside again! Thanks to a local fireplace install company! I kept the Klein CO sensor running for a couple of hours and no CO!!! ... show more
Reviewed in the United States on February 10, 2025 by Tim
    • Happy with this.
Style: Meter
I've got a few Klein tools like this. I'm using this to monitor my out building while running a Mr. Heater 75k - 125k propane heater. All is good. I tested this unit in my garage after running the car for 1 minute. It showed the accumulation of carbon monoxide (dangerous levels). The Mr. Heater runs soclean I wanted to see a reading greater than zero. LOL ... show more
Reviewed in the United States on February 4, 2026 by Jim

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