20x21x4 Air Filters

Sort by:
Products   MERV Rating Filter Life Annual Cost Value Pack
MERV 8 20x21x4 SpiroPure O
MERV 8 Pleated Filters (6 Pack)
  • $168.95
  • 6 Filters
  • ($28.16 / filters)
MERV 8
Learn more
3 Months $112.63
Best Value!

$168.95
6 Filters

($28.16 / filter)
MERV 11 20x21x4 SpiroPure O
MERV 11 Pleated Filters (6 Pack)
  • $217.60
  • 6 Filters
  • ($36.27 / filters)
MERV 11
Learn more
3 Months $145.07

$217.60
6 Filters

($36.27 / filter)
MERV 13 20x21x4 SpiroPure O
MERV 13 Pleated Filters (6 Pack)
  • $230.66
  • 6 Filters
  • ($38.44 / filters)
MERV 13
Learn more
3 Months $153.77

$230.66
6 Filters

($38.44 / filter)
20x21x4 Odorban SpiroPure F
MERV 10 Odor Eliminator Filters (6 Pack)
  • $285.72
  • 6 Filters
  • ($47.62 / filters)
MERV 10
Learn more
3 Months Learn more
about odor eliminator filters
$190.48

$285.72
6 Filters

($47.62 / filter)
MERV Rating - Contaminant Removal Guide
MERV Rating   8 11 12 13
Lint & Dust  
Dust Mite Debris  
Pollen  
Mold Spores  
Pet Dander  
Auto Emissions  
Smoke  
Tobacco  
Bacteria  
Note: equals efficient removal of contaminant by filter.