How does a storage water purification system like 'pure it' kill bacteria and viruses without having uv' or ro?

there is a water purification system named 'pureit' in India which claims to provide water without viruses and bacteria, comes with a germ kill battery i am not able to understand principle behind its calim killing bacteria and even viruses without having ultravoilet or reverse osmosis treatment. how does it kill the organisms in water?