Klein Tools NCVT-1 Voltage r, Non-Contact Voltage Detector for AC Voltage, Low Battery Indicator and Auto Shutdown, Batteries Included

In a word this product is garbage and is being sent back immediately to Amazon. I also bought the Fluke product thinking that I'd keep both if both worked OK. The Klein product continually went off (indicating live wire) when romex was dead. Yea, the Klein has 100% sensitivity and 0% specificity to put it in technical terms. Just manipulating the device would cause it to go off. The Fluke on the other hand has been 100% accurate (no false positives and no false negatives). The Fluke product is twice the price of the Klein but obviously worth it. The Fluke is so good that it will tell you which side of the romex is live and which is dead (i.e., the line side and the load side of the romex). This one is a no brainer, pass on the Klein and get the Fluke.

I’m happy that I tried this on a known hot switch before using it anywhere else while working on my house. It never senses voltage. I tried two new batteries and multiple switches. Even on exposed wires this never sensed any voltage. Extremely dangerous. Amazon didn’t send me the necessary information to return it so I threw it and my money away. I know Klein is supposed to be the best but this was a huge bummer. Watch the video and judge for yourself. Maybe spend the money on a higher end Klein tester or go with another brand.

Unpredictable, works sometimes, sometimes not. Won't detect voltage in a live outlet. False alarms on conductors with an open breaker. Sometimes it beeps when turning it on, other times it doesn't. Turning it off is also inconsistent, sometimes it turns off with a slight touch of the button other times it won't shut down unless the button is held for several seconds. Not the tool I want to use before I touch something that could still be energized. Cannot trust this thing. Returning it.

Professional electrician for 42 years. This is the real deal for non-contact voltage detection. My only real complaint, and it is significant, with this tool is the switch. The on-off switch is its weakest point. There are two types of switches on these devices. The one with the switch near the testing end is pretty reliable. The one with the switch at the end where the batteries are installed is a REAL problem. I have purchased 5 or 6 of the ones with the switch at the battery end, and frequently need to take them apart to "tweak" the switch. It seems the switch easily becomes misaligned and either the button doesn't contact the internal switch or the electrical connection is compromised. VERY annoying! I have learned that I'd better have at least 3 of these available at all times. If they fall from your pocket onto a hard floor you will likely find it's time to "tweak". After a few tweaks, you may not be able to get it to return to operational status. This is the reason for 3-star rating. (Wish they had 1/2 stars. It really deserves 3.5 stars) If they would warrantee the models with the stupid read end switch, it definitely would be FIVE STARS!As for accuracy, these are GREAT! When you get close to an energized wire they beep and the light changes color. When you need to know what wire is what, these are a valuable tool. My only complaint with the accuracy is that in a multi-wire circuit, (like a 3-way circuit) it is somewhat too sensitive, making it difficult to isolate the actual HOT wire from any other ungrounded, but actually NOT energized conductors. It is a minor issue, and certainly does not make the tool unusable.If you get one with the switch near the front you're good to go. If they send you one with the switch on the battery end, do yourself a BIG favor and return it. And remember. DON'T drop 'em!

I have used Kline tools for over the past 40 + years and have always been satisfied with them. That is until I bough this one. I needed a cheapo small non contact tester to just have in the truck for those last minuet situations that did not require a better more expensive. The first one would not even shut off so it went back. When I received the replacement unit it would shut off and on while it was in use. Thats what I get for going cheap. Maybe other folks have had better luck with this unit, but not I. Dont like electric shock therapy. Except maybe on Fridays, then I get to go home early.