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21x26x4 Lennox X6667 / X6669 Air Filters

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Products   MERV Rating Filter Life Annual Cost Value Pack
21x26x4 Lennox MERV8 SpiroPure F
Lennox Compatible (MERV 9)
  • $50.99
  • 2 Filters
  • ($25.50/filter)
MERV 8
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12 Months $25.50/yr
Best Value!

$50.99
2 Filters

($25.50/filter)
21x26x4 Lennox MERV11 Quality Filters
Lennox Compatible (MERV 11)
  • $62.99
  • 2 Filters
  • ($31.50/filter)
MERV 11
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12 Months $31.50/yr

$62.99
2 Filters

($31.50/filter)
21x26x4 Lennox MERV13 SpiroPure F
Lennox Compatible (MERV 13)
  • $57.99
  • 2 Filters
  • ($29.00/filter)
MERV 13
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12 Months $29.00/yr

$57.99
2 Filters

($29.00/filter)
21x26x4 Lennox OdorBan Quality Filters
Lennox Compatible (OdorBan)
  • $64.99
  • 2 Filters
  • ($32.50/filter)
MERV 8
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12 Months Learn more
about odor eliminator filters
$32.50/yr

$64.99
2 Filters

($32.50/filter)
MERV Rating - Contaminant Removal Guide
MERV Rating   8 11 12 13
Lint & Dust  
Dust Mile Debris  
Pollen  
Mold Spores  
Pet Dander  
Auto Emissions  
Smoke  
Tobacco  
Bacteria  
Note: equals efficient removal of contaminant by filter.