FilterBuy 17.5x27x5 Trane Perfect Fit BAYFTFR17M Compatible Pleated AC Furnace Air Filters (Pack of 2). AFB Platinum MERV 13. 17.5x27x5 Trane Perfect Fit BAYFTFR17M Furnace Filter / Air Filter - AFB Platinum (Merv 13). (2 Pack) Specifically designed by AFB to replace Trane Perfect Fit BAYFTFR17M filters Best of breed filter, small particles and bacteria Pack of 2 Filters Merv Rating of 13