With a lifespan of up to 300 charge cycles, this pack of two batteries is equivalent to over 4000 single-use batteries (In GP's internal lab test, compared to GP Super Alkaline batteries in digital cameras). Pre-charged and ready to use. After 12 months from charging, it retains up to 50% of its energy. With an operating temperature ranging from -20 C to +50 C, it ensures reliable operation even under extreme conditions.