Katadyn Micropur MP1 Purification Tablets - 30 count - Effective against all microorganisms. Fresh tasting water - no unpleasant taste. Meets EPA purification guidelines. Effective against: Microorganisms, Bacteria, Protozoa, Cysts, & Viruses Purification Method: Chlorine Dioxide Tablets Output: 1 tablet treats 1 liter of water Capacity: 30 tablets per pack = 30 Liters 4 hour treatement effectivness time 5 Year shelf life from manufacture date