here's the second in the lot of TK goodies from SDS/ AA please see other post for abbreviations.
This is commonly know as a background & or that miss-noma "Stunt" helmet, essentially the helmets worn in the background by the extras in starwars. The back & top of the helmet are quite possibly not from real screen used molds so too the same as the face plate. originally 50 or so of these helmets were made, then the molds were "re-worked" to make the 6 principle actors helmets "hero lids" 
the differences between the background & principle actors helmets are the backgrounds have longer grey painted frowns, more teeth holes are cut, the black rubber brow is lower, they have flat green film gel strips instead of bubbled lenses & there is only one screw fixed to the round body of the ear caps.
the differences between the background & principle actors helmets are the backgrounds have longer grey painted frowns, more teeth holes are cut, the black rubber brow is lower, they have flat green film gel strips instead of bubbled lenses & there is only one screw fixed to the round body of the ear caps.The assembly is fractionally better placed than the other SDS/AA lid but not by much, the back & cap portion of the helmet is also much larger.
