RunTru by Trane A801X (A60K) furnace filter sizes
A801X (A60K) furnaces take 14 x 25 or 16 x 25 or 16 x 25 x 1 filters, depending on cabinet width and return.
Pick your full model number below for the exact size.
A 16 x 25 filter (side return) or a 14 x 25 filter (bottom return) or a 16 x 25 x 1 filter (single/any (catalog) return)