EXTREMELY POWERFUL Ni - MH RECHARGEABLE BATTERIES: eneloop pro AA high capacity Ni-MH pre-charged rechargeable battery deliver up to 2550m - Ah typical, 2450m - Ah minimum; eneloop pro AAA high capacity Ni-MH pre-charged rechargeable battery deliver up to 950m - Ah typical, 900m - Ah minimum LONG LASTING PERFORMANCE: Recharge eneloop pro AA and AAA rechargeable batteries up to 500 times PRE-CHARGED AND READY TO USE: eneloop pro AA and AAA rechargeable batteries are pre-charged at the factory using solar power and maintain up to 85% of their charge after 1 year (when not it use) ADVANCED CHARGING CAPABILITES: The Panasonic CC75 battery charger individually charges each eneloop pro AA and AAA rechargeable battery, resulting in a perfect charge every time 4 INDIVIDUAL LED INDICATORS: The CC75 battery charger features 4 separate LED charging lights, one for each unique charging station. - VERSATILE USB CHARGING PORT: The CC75 battery charger features a USB charging port; 5V 1a that can be used to charge other devices. - BATTERY DETECTION TECHNOLOGY: Each eneloop pro AA or AAA rechargeable battery is analyzed (when the battery is installed) and the charger station for that battery will end the charging process when each battery has been fully charged.