Aquatablets® are a great effective and efficient way to always have a option to get clean drinking water. There light weight, easy to carry, and just one tablet can treat 1 liter of water. 1 strip comes with 10 tablets 3 1/2 tablets treats 1 gallon of water. Aquatabs® are used by all major aid agencies, NGOs, and peacekeeping / defense forces worldwide for the treatment of human drinking water in emergency situations. 15 billion liters of water were treated using Aquatabs in 2008. Aquatabs® are preferred by emergency personnel, and survivalist. You can even use these while camping! Aquatabs® have a long shelf life and can be used where ever you are when boiling water is not a option! Great for prepping, emergency supplies, natural disaster kits, and outdoor activities.