20x24x1 (19.7 x 23.7) Filtrete Ultra Allergen Filter by 3M (4 Pack)  

• Manufacturer  3M
• Part#   2024DC-6 
• 1250 Performance Rating, MERV 11 Rating.
• Convenient package of 4 filters.
• Up to 3 months of filtering performance.
• 25% more efficient than the Filtrete Micro Allergen Filter. 15% better airflow then the Filtrete Micro Allergen Filter.
• Ultra Allergen Reduction Filters