21x25x4 Air Filters

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Products   MERV Rating Filter Life Annual Cost Value Pack
21x25x4 MERV8 SpiroPure O
MERV 8 Pleated Filters (6 Pack)
  • $275.54
  • 6 Filters
  • ($45.92 / filters)
MERV 8
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3 Months $183.69

$275.54
6 Filters

($45.92 / filter)
21x25x4 MERV11 SpiroPure O
MERV 11 Pleated Filters (6 Pack)
  • $275.03
  • 6 Filters
  • ($45.84 / filters)
MERV 11
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3 Months $183.35
Best Value!

$275.03
6 Filters

($45.84 / filter)
21x25x4 MERV13 SpiroPure O
MERV 13 Pleated Filters (6 Pack)
  • $308.97
  • 6 Filters
  • ($51.50 / filters)
MERV 13
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3 Months $205.98

$308.97
6 Filters

($51.50 / filter)
21x25x4 OdorBan SpiroPure F
MERV 10 Odor Eliminator Filters (6 Pack)
  • $306.12
  • 6 Filters
  • ($51.02 / filters)
MERV 10
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3 Months Learn more
about odor eliminator filters
$204.08

$306.12
6 Filters

($51.02 / 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.