Rechargeable Standard Battery, 800mAh, NiMH 1.2V
From Amazon
Panasonic eneloop ready-to use Ni-MH battery, AAA/Micro, 4-pack with blue case, min. 750 mAh, 2100-charge cycle life, high power performance and low self-discharge, rechargeable battery
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Panasonic Eneloop Ni-MH battery Rechargeable + Batterycase (4 pcs, 800 mAh)