A lot of brands make military-inspired watches, but not many make watches for the military. Marathon is one of the latter. And one of those watches is the General Purpose Mechanical, an iteration on its own GG-W-113 Field Watch. That timepiece was created in the 1980s and built to the strict military standard of the day. This newest model is also marketed as an Officer’s Watch and, like the GG-W-113, adorns the wrists of American servicemen and women around the world.