Filters for  980 Series – Kingston, Claremont, Odessa & Lisbon. Approximate life span for the filters (6473-165, 6540-488 and the outer filter for 6541-297) is a year to a year and a half. The inner core (6473-164) should be replaced every 3-4 month. You should rinse the filter biweekly, weekly for heavy usage. Using cleaners like Filter Nu, Spray and Rinse and the Tablet cleaner are great ways to extend the life and keep your water clean and clear. Note, the inner core can not be rinsed or washed.