LifeStraw Family 1.0 Portable Gravity Powered Water Purifier for Emergency Preparedness and Camping Award-winning LifeStraw Family is used by over 13,200,000 people worldwide Surpasses EPA standards for water purifiers: removes 99.99% viruses, 99.9999% bacteria and 99.9% protozoan cysts to 0.02 microns Purifies 18,000 liters/4755 gallons WITHOUT iodine, chlorine, or other chemicals; Clean drinking water for a family of four for 3 years Gravity filter - pour water in the top and clean water comes out the bottom; Comes in a sealed bag, perfect for storing for emergencies Flow rate of 9 -12 liters per hour