There will be no more throwing away perfectly good batteries when our Portable Battery Tester is on the case. This compact, portable battery tester will check the power level of rechargeable and alkaline batteries. Accurately check the remaining power in AAA, AA, C, D and 9V batteries. Simply insert the battery in the tester and squeeze so that the tester's contacts touch the battery. The easy-to-read gauge will tell you whether it's time to replace the battery or if it still has some useful life in it. Do not use the battery tester with leaking or damaged batteries, and only check one battery at a time.