A good eye can pick this up, but when its hidden in a very difficult to reach spot, it often gets over looked. This particular example is in a fuel bay, hidden near a corner that is only visible with a mirror and some flexibility on your part.
Those are navigation lights in the wing tip of a large aircraft. The one on the right is the primary, and the left is there as a back-up in case the first one burns out. They are both designed to give 110 degrees of forward looking green light, off the right hand wing tip. But for some reason I don’t think that will be happening with this set-up. The assembly on the right has been installed backwards, or turned 180 degrees so that it is actually facing aft. who knows how long it has been installed this way, needless to say, I turned it around.