Here is my solution for NLA brown hot air heater hoses. I used USMC Black Leather Dye that I picked up at Tandy Leather Store. I used Acetone to dilute it because that is what I had, but I think they recommend denatured alcohol. It took a couple of coats but it turned out pretty good. The tan cardboard blended with the black and resulted in a slight off black color. Not exactly like the color in prior pics, but looks better than just plain tan IMO. And the price was right, sub $10. If this fades should be easy to re-dye it.
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