This is the best cable exercise that few people know about or do. I’m guessing other names exist for it, but I saw Dante Trudel do it first, so I attribute it to him.
It works by isolating the lats through a long range of motion. I consider it a superior, modern-day equivalent to the old chain-driven Nautilus pullover machine made famous by Dorian Yates.
You do these with a seated pulley row machine, but in an unconventional manner. The key is to get a good stretch when extending your arms before driving your elbows back towards your knees, rounding your back and flexing your lats as hard as possible before accentuating the negative.