No atteries required! LED lantern to be generated by the water and salt Magnesium <mechanism of power generation> - between the carbon of the (+), ion melts by putting salt water which is the electrolyte, () - electricity is generated by moving to + from. Compared with batteries, it is a clean energy and environmentally friendly. (Life of the metal rod) about 120 hours Please replace the salt water to about every 8 hours.