Panasonic eneloop BK-3MCDE battery - 4 x AA type - NiMH

eneloop is a rechargeable battery built on the concept of "for a sustainable lifestyle". It combines the reusable qualities of a rechargeable battery with dry battery qualities which is immediate usability after purchase or long-term storage. The battery will naturally self-discharge, meaning that the amount of energy stored within will gradually decrease, but eneloop offers significantly improved resistance to this self-discharge to provide similar levels of convenience to dry batteries.