I recall that up until the 1960's, manufacturers of electronic enclosures provided their products in only one finish: black crinkle.
Any non-commercial prototype electronics were usually enclosed in one of these products; whence, black boxes.
Yes! ...and today, 99% of the electronic boxes on a/c are still of the "black box" sort.... The only two that aren't, are the one's the bloody press continually call the "black boxes".
Sorry... that's a tangent this thread doesn't need.
