Most people prepare emergency light or flashlight at home or office. But too often, they forget to recharge the battery or no usable battery when in emergency.
Aqumo Water Candle emergency light is the answer. It is designed and made in Japan. Just dip into little water (1 ml), it activates the magnesium-oxygen chemical reaction to power the light. Within 2 seconds, the luminance can be up to 400 lux. The light can continue up to 7 days. Just dip little water every couple days when the light is dimmed to restore the luminance.