LifeStraw Emergency Water Filter
This water filter has a built-in gravity hose attachment with universal threading for squeeze bottles and can remove 99.999999% of tiny particles. It has a long-lasting membrane microfilter that will last up to 1,000 gallons (4,000 L) of water. The price drops from $24.95 to $15.89. Shipping is free for prime members or on orders over $25.