bobble HAF00I20IC01200D Replacement Carbon Filters Plus Infuse bobble has an activated carbon filter which has a slight electro-positive charge, making it attractive to certain chemicals. as water passes over the positively charged carbon surface, the negative ions of these chemicals are drawn to the surface of the carbon granules. These filters are only for the bobble Infuse or bobble Plus This will NOT fit your bobble Classic or bobble Sport Replaceable carbon filter removes the taste and odor of chlorine from municipal tap water, resulting in a cleaner, crisper taste