Chlorine dioxide kills bacteria, viruses and cysts in water including Giardia and Cryptosporidium. These water purifying tablets are the safest and most effective form of chemical water disinfection and unlike chlorine, have no noticeable aftertaste. Treats up to 30 litres of water Kills bacteria, viruses and cysts No significant aftertaste Duke of Edinburgh recommended kit Weight: 40g Volume: Treats up to 30 litres of water (pack of 30 tablets) Dimensions (packed): 65 x 105 x 20mm