Paper explination?

Definitely a cool history lesson in this thread.
I think the "blue" ones are faded black, the real blue ones I've seen have blue rubber bases where they mount to the floor. I've got black ones from a 75 ( retractable shoulder and lap ) in my 73 and they are a smidgen faded in places that make them look a little like navy blue, but down inside the retractors they are black.