The LifeStraw activated carbon filter protects against chlorine, organic chemical matter and odors for improved taste. This filter, compatible with the LifeStraw 2-stage membrane microfilter, is ideal for hiking, camping, travel, outdoor activities and everyday use. Your purchase has impact: one product, one child, one year of safe water. LifeStraw filters are rigorously tested to meet protocols established by the US Environmental Protection Agency (EPA) and NSF International/ANSI. Your purchase has impact. For every LifeStraw product purchased, a school child in need receives safe water for an entire school year.