T-Slot Closure Extrusion?

I’ve got a couple inquires to companies around but hadn’t stopped here first. Has anyone found a push in rubber strip to close the open side of the T-track on the exterior?

I was looking at my rain track on the airstream and thought sliding something in the GFC could keep water, road grime, and other organics from gathering too much in those tracks. There are closures for the 80/20 but the dimensions don’t seem to jive.

I know I’ve seen a post where someone found some stuff that fit the GFC extrusion. Don’t remember if it was here or the Tacomaworld forum. Sorry, probably not all that helpful.

I may have miss remembered, it was only a suggestion to try this stuff:


From post #2219 here:

Gotcha. Thanks for checking. We’ll see what the manufacturers say about small quantity availability. I have access to some commercial window gaskets I’m gonna try next week.