This tricep exercise doesn’t really have a name, as I got it from my friend and its not very common but boy is it good. I like it call it the leaning back cable longhead tricep extensions. This exercise is a finisher, a closer if you will, to cement the final burn in your pump and therefore the proper way to end your workout. So I do this one at the very end of my chest, shoulder, and triceps days and would strongly recommend it. Here is a video of me doing the first part of the exercise with my right arm before switching to my left. Focus on the form!