The Duracell Hi-Speed Advanced Battery Charger can charge 2 AA batteries in just 45 minutes (*Approx. 85% of full charge when using Duracell 1.300 mAh AA NiMH batteries). It gives you up to four hours of use in just 15 minutes of charging (**When charging AA batteries; results vary by device and usage pattern). Its 9 safety features make sure that you can keep going without any worries and after batteries are completely charged, the charger can automatically shut off to prevent from overheating. This charger comes with Duracell’s 10-year guarantee, so you can rely on Duracell’s long-lasting power every day.