The McNett Frontier Pro Replacement Filter GRN-III-50 features Series III connectivity for use with The Frontier Pro filter system. It removes 99.9% of giardia, cryptosporidium and bacteria. The Miraguard antimicrobial technology prevents growth of fungus, mold, mildew or bacteria inside the filter. It is BPA and iodine free and removes chlorine, bad taste and odors. The filter element will last for 50 gallons. Bring one with you on longer trips so you can keep using your Frontier Pro filter.