This is a flak armor vest, with attached shoulders and accompanying shin plates, standard issue protective gear of the Imperial Guard, disparagingly refereed to as "cardboard" by the denizens of 4chan's traditional gaming board. Good thing balls of steel are also standard issue.
This is quite possibly the most difficult and time-intensive costume piece I've ever worked on. Ideally, I would have spread the work out over several months, so that I could work at a leisurely pace and take frequent breaks. This was not to be. Due to the fact that my friend somewhat lacks the spark of artistic furor, I was forced to initiate the construction of this armor barely a week prior to PAX East 2012, for which it was to be worn. Considering the miniscule time frame, I am happy with the result.
We mostly followed Indy Mogul's "sci-fi armor" tutorial, as seen on Youtube. [link]
The armor is composed largely of tough foam taken from interlocking floor plates, cut into the requisite shapes with scissors and box cutters. I used a dremel to smooth out the edges of the pieces. My friend carried out the final assembly using a heat gun to bend the foam into shape, hot glue to secure the plates, and work-grade utility belts for the straps. I painted the armor using hunter green Krylon, then used a stencil to spray white number eights onto the right pec plate and left shoulder, to represent the famous Cadian 8th regiment, or "Creed's Own." The skull-in-temple symbol on the right shoulder was painted freehand with white acrylic. At my friend's request, I used the heat gun again to inflict scorch marks on parts of the armor, to represent las-bolt impacts. The right shin guard features a sheath for a toy knife I had lying around.
This armor, together with my Lasgun prop, is to be worn by my friend in conjunction with my own improved Commissar costume.