This is why Iran's Special Forces still wear US green berets
When looking at Iran's 65th Airborne Special Force Brigade, you might notice a few striking similarities — the yellow enlisted chevrons seem a lot like the the yellow chevrons on old Army greens, for example. Before the Iranian Revolution, their unit insignia looked a lot like the De Oppresso Liber crest that signifies the United States Army Special Forces.
The distinctive green beret worn by the Iranians may not be the same shade of green worn by today's U.S. Army Special Forces, but Iranian special operators wear green for a reason — they were trained by Americans.
https://www.wearethemighty.com/history/iran-special-forces-green-berets