Nazava water filters are suitable for filtering rainwater, river water, tap water and dirty runoff water into potable water. Drinking water is an expensive essential in Indonesia but with a Nazava water filter it doesn't need to be. The filters last for two years before they need replacing. A Nazava filter will save a family of four 250,000 rupiah a month which is a considerable cost. Nazava water filters are used by the UN and are approved by the World Health Organization.