Stop in for a cup of coffee

Question one of the taillight bezels had a taillight wire wrapped in a brownish green looking unknown material. Even had a old white tag with a number, maybe a part number?? It was in great shape and saved it.
When I went back to get the doors today, I found four more taillights sockets with the same wrap, all in great shape.
What color was the old stuff?? Anyone know??
I'll post a pic later.