This dual-chemistry hybrid charger charges any rechargeable alkaline or NiMH battery. This Charger is designed for "charge and store" it holds the charge for up to 7 years. It charges both AA and AAA cells in any combination with ultimate convenience. Plug into any standard USB port to charge. The charger is microprocessor-controlled with a LED charging indicator. Save money and the planet with iGo Green Rechargeable Alkaline Batteries. These batteries provide the versatility and cost of disposable alkalines, but with the added benefit of rechargeability, saving even more money. And with none of the heavy metals found in other rechargeables, theyre the greenest batteries available.