Marathon General Purpose Mechanical.  MIL-PRF-46374G.  34mm. Dual wind. New in box.

* I got this brand new in December 2020 direct from Marathon, part of my collection, unused, new in box.

* 24 jewels Japan movement. Dual wind.  I tested the accuracy, and the watch looks to have gained 7 seconds after 20 hours, when compared to a quartz watch.

* Casing measures approximately 34 mm wide, without measuring the crown.