Two stages of filtration Hollow fiber filter lifespan: 1000 gallons / 4000 liters Ion exchange filter lifespan: 25 gallons / 100 liters The replacement LifeStraw Bottle Filter Set in size small fits the Eddy+ 20 oz filtered by LifeStraw bottle made with Tritan Renew plastic. Water passes through two separate stages of filtration - the hollow fiber filter removes bacteria, parasites, and microplastics and the ion exchange filter reduces lead, bad taste, chlorine, and other unwanted chemicals.