Oh by the way, this is the special version that does not have a gas port. The argon seeps through the actual threads themselves (hard to see in the pic)
Just Kidding! They moved the gas port to the top of the head! Very clever those Heavy Hitter boys! If I had to guess, the gas path splits up into a Y, then recombines at the top of the torch head. Seems that would provide the best uniform cooling, but it's just speculation on my part.