Quantity: One Digital Hearing Aid Button Cell BATTERY TESTER on Key Chain. This handy tester measures the remaining power of many common hearing and aid and button cell batteries. The unit is self powered, drawing the energy it need from the battieries tested. Simply insert a battery "+" up and gently push the battery against the metal bar under the words "Battery Checker". The digital LCD screen displays a bar graph showing the remaining power for each battery tested. And, as an added value the Battery Checker has a slide-out battery compartment which can hold 2 extra batteries, so you can always have a spare. And of course, the handy key chain link means you can keep the tester with you at all times, no matter where you go. NO BATTERIES INCLUDED
