This led emergency lights can be said to replace candles and matches the best lighting items. There are few candles and matches for modern people at home, one is not environmental protection and the other is insecurity. Candles and matches are afraid of water, will be extinguished with water, on the contrary, H2O emergency lights rely on it is water! H2O emergency lights do not need to plug in the socket, do not need lithium-powered, activated by water! You can put it Into a glass of water, or to its battery compartment water, H2O emergency lights will be lit. Add water once, it can last for 72 hours.