CopperTop Alkaline Batteries with Duralock Power Preserve TechnologyGet long-lasting, reliable power for the devices your business uses most. CopperTop batteries are engineered to deliver just the right level of power for most electronic needs. CopperTop batteries contain no added mercury and are rated for reliable operation in extremes from -4°F to 129°F. Individually date-coded and up to 10-year freshness guarantee in storage. Battery Type: Alkaline; Battery Size: C; For Use With: Everyday Electronic Devices.