Panasonic eneloop pro AA rechargeable battery can be recharged up to 500 times. eneloop pro rechargeable batteries are 2550mAh type, Ni-MH pre-charged rechargeable batteries eneloop pro rechargeable batteries are multi use, come pre-charged with solar energy and are ready to use When stored as per instructions/in its unique case, Rechargeable eneloop pro maintains up to 85% of its charge after 1 years in storage (when not being used) The No Memory effect in eneloop pro AA rechargeable batteries allows the batteries to be recharged when fully or partially discharged Panasonic eneloop pro rechargeable battery works in extreme temperatures ranging from -20 °C to 50 °C temperature range [Operation time will be shorter than that at room temperature. Operating time varies according to equipment] eneloop pro batteries are best for DSLR flash and digital cameras. But they can also be used in other high-energy consuming products like radio control cars and other wireless devices Panasonic eneloop pro rechargeable battery provide optimum performance when paired with Panasonic's eneloop chargers