Duracell CopperTop all-purpose alkaline batteries are not only dependable, they're also long-lasting. You can take comfort in a ten-year guarantee (five-year guarantee for 9V) in storage. They're great for many of the devices you use on a daily basis. From storm season to medical needs to the holidays, Duracell is the battery you can trust. Battery Type: Alkaline; Battery Size: 9V; For Use With: Everyday Electronic Devices; Voltage: 9 V.