NAME THAT PART

I am restoring a '71 Demon. This weatherstrip came in a long continuous piece, about 20 feet long, and I know the guy I got it from cut it off of an even longer piece. LOL...I've been rounding up parts lots for this build and some of the stuff isn't even for the car. I hate passing on stuff, and finding out later that I needed it......I will never buy an incomplete car again!:)