An Original Trane Perfect Fit Filter Is An Integral Part Of A Trane Home Comfort System. The Trane Perfect Fit Filter Features A MERV 8 Rating For The Reduction Of Dust, Dirt, And Various Allergens In The Air, And The Improvement Of Indoor Air Quality. For The Millions Of Particles In A Typical Home’s Air, An Original Trane Perfect Fit Filter Traps More Dust, Pollen And Bacteria Than Typical Filters. They Filter Out Up To 15x Better Than Standard Filters.