AA Battery Tester Small Batteries Voltage Pen Usb for AAA D 9-volt

This item is a checker tester for 9V, D type, C type, AA, AAA. With it you can easily get the current volt of the tested battry, and know which batteries to keep and which to throw, place your between the two points of the tester, and the pointer display will indicate that whether there is a need to be replaced.

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