For such an iconic and timeless piece of industrial design, the headsets don't seem to be discussed much! 
I take it they are some kind of 3M Peltor headset (or copies thereof?), so it's so surprising to see a lack of 3M Peltor branding or sponsorship anywhere on any of the teams. Or is the Peltor even the "original" at all, if not which was the original noise isolating headset (+ wireless transmitter) which introduced the iconic double wire frame design?
Ferrari seem to use a somewhat less cumbersome model, without the double spiral cords but instead a simple single-sided cord:
