This WorkPro battery tester can check the remaining power of AA AAA C D 9V 1.5V Batteries. It's easy to use and adjusts to accommodate different sizes. The universal battery tester gives accurate results for a variety of 1.5V, 9V and button cell batteries. Additionally, it has a color-coded scale to show the power level. No need for power supply, you can quickly determine whether the 1.5V AA battery, AA battery, 9V square battery is sufficient. It is compact and easy to carry, and it is easy to put in a pocket or backpack.With indicator plate, the pointer directly displays the measurement result, and it is easy to check the battery status. Easy to use, simple to operate, just insert the battery, please pay attention to the positive and negative poles. A battery capacity measurement tool that is very suitable for home use and can tell you whether the battery is good.