See...in many multi-battery devices, not all the batteries discharge evenly – it's quite common to find one or more perfectly good batteries from a set that don't need to be thrown out (just yet anyway). On top of this, if you find you've got batteries lying around at the bottom of a drawer or box, there's no better way of quickly sorting out the duds than with our All-In-One Battery Tester. Use rechargeables? Great, our battery checker will tell you when it's time to recharge them, which reduces...