Tier1 Replacement for Trane 21x26x5 Merv 13 BAYFTAH26M Air Filter 2 Pack Upgraded media rated at MERV 13 to capture 90% of particles, 1 microns or smaller in size Replacement for: Trane BAYFTAH26M, FLR06074 and Honeywell TRN2621T1 Up to twenty times more effective than ordinary fiberglass filters. This product is listed and rated by Underwriters Laboratories as U.L. Class 2