October 7, 2021
This seal comprises two materials:
1. Rigid plastic portion (about 0.25 inches tall) that inserts into a thin slot in the window. Rigid portion also includes a feature about 3/4 inch in length that is intended to mate with the window bottom surface.
2. Flexible rubber portion is round shaped ( about 1/4 inch in diameter) that is filled with foam.
I don't have an install date for these windows but I suspect they are at least 20 year old perhaps Pella windows.
I have spent hours looking for this seal on the internet but haven't yet found one that comes even close.
October 26, 2021
Thank you Casey. I will give that seal a try.