Duracell CopperTop All-Purpose batteries are not only dependable, they're also long-lasting. You can take comfort in a 10-year guarantee (5-year guarantee for 9-Volt) in storage with Duralock Power Preserve Technology. They're great for many of the devices you use on a daily basis. And from storm season to medical needs to the holidays, Duracell is the number 1 trusted battery brand so you know its a battery you can trust. CopperTop batteries are available in AA, AAA, C, D and 9-Volt sizes.