Lightweight and durable, the Duracell CR2 Lithium Photo Battery is designed specifically with the needs of photographers in mind. The battery is part of Duracell's Ultra line, which contains lithium iron disulfide, making it reliable in all weather and perfect for cold-climate photographers. Although mostly used in cameras, the CR2 battery is also required for some photography equipment, such as flash triggers and shutter remotes. Given their limited use in non photography-related devices, the Duracell CR2 Lithium Photo Battery is more difficult to source in bricks-and-mortar stores than more common battery types, however given their long shelf life of up to 10 years, this is certainly a battery that can be bought in bulk and kept aside with the camera until your next photography .
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