Filters-NOW RZ14ALL=RPC Panasonic Air Purifier Carbon Pre-Filters Fits all Panasonic room air cleaners that require a carbon pre-filter. Large 15-3/4 x 48 cut-to-fit activated carbon sheet! Helps remove large particles and reduce common household odors such as cooking odors&#44; tobacco smoke Makes 1 to 4 pre-filters depending on the model. For optimum performance&#44; replace pre-filter every 2 to 3 months.