Very useful battery tester. Works well and saves money by preventing throwing away batteries before they are fully depleted. I sometimes have one bad battery out of four in an electronic gadget and I have the reflex to throw them all out when the gadget isn't working properly. This tester identifies the weak one which I then replace it with a fresh one to return to proper power level.

I bought two of these devices. One for our household the other for my daughter's. Recently on a visit to my daughter's, a new child's toy needed batteries. My daughter hauled out two AA batteries and the toy was still inoperative. We tried two more pairs. Same result. Stores were closed so needless to say the new toy excitement turned into regret. Admittedly, my daughter confessed the batteries have been in the drawer a long time. Now if we'd been at home I'd have pulled out the old multimeter I have. But that's a pain to haul out and test batteries at times. So when I saw these testers and at a reasonable price I jumped at them and they haven't let me down. I was very surprised to see new AAA batteries purchased from a big online retailer recently, when tested, only proved 1.2vdc. I checked that with the multimeter and it corroborated the testers results. That pack of new batteries were all less than 1.5vdc. So moral of the story is, it's nice to have a quick test for batteries and be comfortable with what it displays as accurate. Quick easy verification when you root through the junk drawer to find that battery for the remote control etc. Build quality of this tester is reflective of the price but all in all a worthy addition to the odds and ends drawer knowing it'll come in handy when required.

bon petit testeur à batterie, ne prend pas de place

Works very poorly. At first I was able to test AA and AAA batteries (1.5V) but after testing a 9V battery, the screen won't display any voltage from my 1.5V batteries. Disappointing.

gave myself a present, works great

easy to use. it works great for AA, AAA, 9V and etc... Battery. handy to check battery level. great simple product for battery check. would recommend to buy!