From the Manufacturer The power you've always trusted now comes guaranteed for up to 10 years in storage. Duracell with Duralock Power Preserve™ Technology means our CopperTop batteries deliver long-lasting power when you need it most. Many of the battery-powered devices you use in your home are powered most efficiently by CopperTop batteries.Product OverviewDuracell with Duralock Power Preserve™ Technology means your AA, AAA, C, and D CopperTop batteries have a 10-year guarantee in storage.CopperTop batteries have been engineered to deliver just the right amount of power for your household devices. They’re reliable sources of power for flashlights, toys, alarm clocks and more. Duracell CopperTop batteries with Duralock Power Preserve™ Technology are available in AAA, AA, C, D and 9-volt sizes.CopperTop batteries can power most household devices, including:ToysRemote controlsFlashlightsClocksRadiosSmoke alarms*Length of power preserve guarantee in storage varies by battery type. Ultra (AA/AAA), CopperTop (AA/AAA/C/D) and Lithium Coin are 10 years. CopperTop (9V): 5 years; Rechargeables and Alkaline Coin Button: 3 years; Hearing Aid (Alkaline): 4 years.
