Some 25 years ago I purchased an Air Force surplus Saunders 20 x 24 adjustable easel. Not being set up to use it, I never opened it. As I unpack a lot of darkroom gear to get it ready to dispose of, I finally opened the easel. It's the standard Saunders 20 x 24 easel, the one with two adjustment knobs on the side and two on the bottom. But one thing is unusual. The base has a black vinyl surface laminated to it. In other words, the easel is totally black except the standard Saunders yellow is visible in the paper load slots. Does anybody know what I have and why is was made black for the military?