Help Finding Furnace Filter

[DIYhome48853]

Filter Size is 18 x 20 x 1.
I did the best video footage I could for it is very cramped in the attic.

This video is approx. 2 minutes in length:

https://drive.google.com/file/d/1rutjcuUwNV0VEa3N2ZqoAH8Z328okQC6/view?usp=drive_link