April 2018 card of the month - Black Scribble w/ No F
I've seen it also referred to as the 'Lite Loop' or 'Airbrushed F' version. Of the 3 most common black scribble versions - this is likely the less common of them. Probably one final attempt at obscuring the FF with a scribble before the Black Boxes arrived. I've seen a few saw-cut versions as well.