Won't handhold here; Randolph Engineering (RE) are a U.S. DoD supplier of aviation flight glasses, proudly based in Randolph, Massachusetts. ACL took a tour of the plant and posted a great photo essay last year, as did OMS (see here).
Recently saw you can order the glasses from their site with any combination of lens, finish, arms etc... Pretty great.
Below is a special make-up of the Sportsman with bayonet temples (my preference) and a black treatment. For some reason I imagine Nick Maggio being all over these...
You can see it more easily in the standard gold treament here (v nice too); the prominent bridge, or sweat-bar, that was originally developed to hold the sunglasses away from your eyes thus reduce fogging and literally stop sweat while hunting. This style is descended from a shooting frame. Intel from Susan at RE. thx.