Alexapure Pro Water Filters - 4 PackOur best water filter value! Stock up on our innovative, gravity fed Alexapure Pro filters and save. Certified Alexapure Pro Filter 4 Pack: Filtration capacity up to 20,000 gallons Up to 4x flow rate vs. single filter Reduces up to 99. 9999% of 200+ contaminants Entirely gravity fed, ideal for off grid or emergency use 100% Made in the U. S. A. The filter is tested to NSF ANSI Standards and uses NSF FDA approved materials. Once you tap into the