Get dependable, long-lasting power from CopperTop batteries with Duralock Power Preserve Technology. These batteries have been engineered to deliver just the right level of power for most of your household needs. Plus, they now have up to a 10-year guarantee in storage.* Many of the devices you use in your home are powered most efficiently by Duracell CopperTop batteries with Duralock, including: Toys, Clocks and radios, Remote controls, Smoke alarms, Flashlights, Portable Electronics, Calculators, Wireless Mice & Keyboards and many more. Buy this and Save $28.04 Off on a Duracell 30 AA + 10 AAA Batteries Bulk for $11.95 with free shipping at Rakuten.com.