Size:48 Count Duracell CopperTop All-Purpose Alkaline batteries are not only dependable, theyre also long-lasting. You can take comfort in Duralock Power Preserve Technology that gives you a 5-year guarantee in storage. Plus, theyre great for important devices in your home like smoke and carbon monoxide detectors. And since Duracell is the #1 trusted brand of first responders and firefighters, you know theyre a battery you can trust.