Arb rapid pure universal purifier bottle adapter< FEATURES:-Turns your favorite wide mouth water bottle into an advanced water filter & purifier to provide you w/ safe,great-tasting water-Works w/ NalgeneA(R), CamelBackA(R), Hydro FlaskA(R) & Klean KanteenA(R) Other Features: Purifying water bottle filter adapter, twist this water bottle filder adapter on to your nalgene for easy water purification with no waiting