$67.99 2 Pack of Granular Activated Carbon 5 Micron Water Filter Cartridge by Aquaboon Water Filters 
Amazon.com: Filter Cartridge, Water, 0.5 Micron: Home Improvement
DUPONT 0.5 Micron Rating Water Filter Pitcher Cartridge, 2-3/4 Diameter, 6 Height, 0.26 gpm 
