Filter Size: In-Line Portable Water Filter. 5.5 inches Long X 1 In. Diameter. Easily carried in our hydration packs. Filter Capacity – Gallons: Rated to Filter Up To 50 Gallons of water filtration – You now have a much greater range while hiking. 50 gallons can take you a long way! Tested and Certified: Removes >99.9% Cryptospordium & Giardia.