TM Multi-Function Battery Charge Tester 1.5V 9V Button Cell Eliminate guesswork on battery charge status for electronic devices Easy to use, compact tester instantly shows strength of D, C, AA, AAA, 9V plus 1.5v button cell Saves time and money - don't throw away or waste 'good' batteries Identify device issues, dead bulbs, etc. Battery free - powered by battery being tested