I've had this image (sort of) in my sketchbook for a.few years. So I've dug it out and modified it to make into a corner piece.
They are pfeil tools. They are lovely yo work with. They come in sets of 6 or individually. I have set C.
I really like this Tricia. The tools your using, who makes those?
So lovely and precise useful for a short note let
Here's the final print.