2GFN2
Air Handler 2GFN2 Mini Pleat Air Filter 20" x 24" x 4" 95% MFRM FG MERV 14
The model 1620 has a straightforward design that works well in warehouses.
Air Handler Mini Pleat Air Filter 20" x 24" x 4" 95% MFRM FG 2GFN2
A nice touch with BHC Parts is the reusable bag they ship small parts in.