Walmart continues to offer the 3M Filtrete Allergen Defense HVAC Filter 3-Pack for $17.88. Opt for in-store pickup to dodge the $5.99 shipping fee. That's tied with last week's mention, $9 off list, and the lowest price we could find. These filters feature an 800 MPR and last up to three months. They're available in select sizes from 12" x 24" x 1" to 18" x 24" x 1".
These little-known sections of Amazon.com are true hidden gems for deal-seekers and impulse shoppers alike.