Lifesystems Chlorine Dioxide Water Purification Tablets Easy to use, an effective way to treat clear running stream water. Always check for debris, any particles should be removed before drinking. Chlorine Dioxide Tablets are the safest and most effective chemical water disinfectant available. They kill bacteria, viruses and cysts in water (Including Giardia and Cryptosporidium) 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 Contents: 30 foil sealed tablets. Once opened use within 36 months. This product is specifically recommended by the D of E charity as the best choice for those taking part in their bronze, silver, or gold awards