So they are private purchase? So a tailor sold a set of boards with fat sloppy piping, sewed one with white thread, the other with dark thread in two different methods? Remind to avoid that tailor I am not saying the straps are fake or the devices are fake, I am saying they do not belong together, someone has made these up using a 1800s great coat strap in my opinion. Actually your boards are backed in black, it is the strap that is blue which is right for an uberrock. But for a NCO, who would be wearing field grey, blue backing and blue straps for the loop makes zero sence.