In books about the SAS, they seem to blur or block the faces of the operators often. Maybe that's why he doesn't have any insignia or name tags.

I think you need a couple of years in regular military before attempting entrance into the SAS, like the Army's Green Berets. The SEALs can try out for BUDS soon after they complete basic, I think.

If he's SAS, the lack of rank wouldn't be surprising.  SAS routinely goes around in sterile uniforms.  The rank structure in SAS is pretty simple as well.  The rank you held before entering the regiment doesn't matter once you go in (other than officers).  A Regimental Sargeant Major who chose to enter the SAS and passed selection, would be assigned to the slot that best suited his talents.  If there wasn't a regimental SM slot available, he would get busted down in rank and pay to the slot that does suit him.  His rank is restored when he leaves the regiment.   Senior sargeants are known for giving up substantial rank and grade to join the regiment.

SAS troopers tend to be older and more mature than those occupying similar ranks outside of the regiment. Considering the level of skill and personal discipline needed to pass selection and enter the regiment, you aren't going to see that many 20 year olds, or even 25 year olds.  30 is probably closer to the average age.

Aussie SAS

[img]http://www2.ttcn.ne.jp/~camouflage/image/australian_army_sas_desert.jpg[/img]

I second him being Aussie

Further evidence of Aussie nature is the helmet (like ours... not the British kevlar dome).