eneloop AA and AAA NiMH ready to use rechargeable batteries utilize Panasonic advanced rechargeable battery technology allowing them to be recharged up to 2 100 times. eneloop AA and AAA rechargeable batteries deliver consistent power performance maintain 70% of their charge for up to 10 years come pre-charged by solar power (at the factory) and are ready to use out of the package. These eneloop batteries also feature extreme temperature performance down to -4 Fahrenheit. Pair eneloop and eneloop pro AA and AAA batteries with Panasonic advanced quick advanced or super quick advance eneloop chargers to maximize your rechargeable battery experience.