$67.99 Aprilaire 413 Air Filter for Aprilaire Whole Home Air Purifiers, MERV 13 (Pack of 4) - Walmart 
Aprilaire 413 Replacement Air Filter - 2 Pack for sale online | eBay
Aprilaire 413-CBN Odor Reduction Filter Replacement for Whole-Home Air Purifiers, MERV 13 with 
