The Trane BAYFTAH21W1A is the correct pre-filter for the following enclosures:
The Trane Perfect Fit BAYFTAH21W1A Prefilter 21.5x21x1 is an OEM replacement filter from Trane that features a MERV 5 rating for the reduction of airborne particulates. This Trane Perfect Fit filter fits 21 1/2" enclosures and measures approximately 21.5" x 21" x 1". A major feature of this Trane furnace filter is that it is both washable and reusable, allowing for an economical alternative to costly air filtration.
Trane Perfect Fit BAYFTAH21W1A Prefilter 21.5x21x1 specifications: