Product Description: Aquatabs water purification tablets quickly and reliably purify drinking water on-demand. They&';re effective against viruses, bacteria and Giardia cysts, providing safe drinking water in just 30 minutes. Ideal for ultralight backcountry travel, they&';re also great for international travel and emergency kits. And because they&';re individually packaged, they travel well, making them the ideal emergency back-up to any microfilter. Features: Effective US EPA-registered in all 50 states; effective against viruses, bacteria and Giardia cysts. Fast: 30-minute treatment time. Efficient: Each tablet treats up to 2 quarts of water depending on conditions. Ideal For: Ultralight backcountry travel, international travel and emergency kits. Available In: Box of 30, or as 50 bulk.