It’s not your batteries at all. With this tester, you can make sure of that. Test the voltage of AA, AAA, C, D, 9V, and even mini cell batteries. Voltage range on the back of the tester will help you determine the quality range of Good, Low Power, or Replace. Save some money on all those batteries you’ve been buying recently and now test them first! If they’re still good, not only are you saving money on those batteries, you’re also saving the environment by not throwing away something good. So be kind to your wallet and to nature and pick up this compact tester today! For 1.5V and 9V batteries,read off LCD. For 1.5V mininature cells,read off LCD. IF LCD does not display,check that battery is touching both contacts before assuming that it is completely dead. This Battery Tester is activated by the battery being checked.Keep taet times as short as possible, to avoid unneccessary battery drain.