UMLIFE 4PACK Battery Tester, Universal Battery Checker Small Battery Testers for AAA AA C D 9V 1.5V Button Cell Household Batteries （Model：BT-168 PRO）

No more throwing away batteries that are still good. Often, when changing batteries there is still a good one in the bunch. This battery tester is cheap, accurate and high quality.

2 for the price of 1! Used to pull out and fumble around with my multi meter to check simple alkaline AA and AAA batteries. But no more with these easy to use testers, pop them in and BAM there's your voltage read out with a DIGITAL GAUGE! Don't make the mistake and get ones with a meter showing bad/poor/good. Get THIS ONE that gives you a real voltage on the LCD. So much better to know if you can still use a battery or not. All in all the best deal on the planet with these!

Updated: I ordered these because I got tired of digging out a multimeter when I wanted to know the actual voltage remaining in an old battery. I originally reported that the battery tester stopped displaying at voltages below 1.2v. That bothered me though so I decided to retest to see if I received defective battery testers. It turns out that the problem was not with the battery testers but with a new multimeter that I used during the test. I got replacement batteries for an old, proven Radio Shack multimeter and used it for the retest. It showed that my AA test batteries only had 0.3v remaining; they were dead batteries. My new multimeter incorrectly reported the voltage as 1.2v. Based on this, the blank screen is the correct behavior for the battery tester because they powered by the voltage of the battery being tested. As verification, I also tested the old button batteries from the RS multimeter. Both the battery tester and the RS multimeter both reported an appropriate 1.1v while my new multimeter provided a more creative voltage reading. Apparently my new multimeter is not very accurate at low voltages. In the end though, my rating remains the same. If you want to see the remaining voltage of a battery, these battery testers are accurate enough and quicker to use than finding and using a multimeter. Most of the time though, you just want to know if a battery is still good and usable. That check can be made quicker and easier with the version of this tester that has an analog dial display.

works well. seems to measure voltage accurately and <2% off

These are very useful and work as advertised. It is so much easier to test batteries with them rather than a test meter, as others have stated. I highly recommend them.

It takes some fiddling turn make it connect

I am constantly needing to check the status of my batteries and this tool make it easy to check them

Gives the exact voltage of battery not just a "good" "Replace" reading like the analog types. This will give a good idea about how much charge is left. I tested the reading with a power supply that gives the output voltage and they matched exactly, so it is actually more accurate than I thought such a cheap device would be. It is cheap plastic and sometimes requires a firm pressure to read the voltage depending on battery but what would I expect for the price? Good to test from 1.5 cell to lithium ion like an 18650 and also 9V battery.