Energizer 8 Hour Charger with Rechargeable AA 2-Pack and AAA 2-Pack Input Voltage: 120V AC The charger is compatible with any AA or AAA rechargable batteries. COmpatible with AA NiMH Batteries (maximum capacity of 2500 mAh) and AAA NiMH Batteries (maximum capacity of 850 mAh) Accomodate maximum 4 AA or AAA batteries at once. Sliding mechanism. Great for travel when it is slide in making the compact size