Prime Members: Winix 115115 True HEPA Filter A (Fits C535, 5300-2, P300, 5300) $21.85 + Free Shipping

Amazon has Winix 115115 True HEPA Filter A (Fits 5300-2, C535, 6300-2, P300) for $21.84. Shipping is free with Prime or on $35+ orders. Price is $6.15 lower (22% savings) than the typical price of $27.99.