Added to what Willie said. The post-37 FET kept the blue shirt and red beret of both their former entities as a 'dress uniform', but in line units the standard army shirt appears to have been worn, with blue epaulettes and collar, or just the epaulettes, depending on the time period, it changed over time. I presume that the blue shirt must have made a good target. Might have been the same with the beret, I don't really know.