This is a Military issue Pocket Watch by CYMA  

The Face that has fluorescent material Arabic Numerals and Hands with fluorescent material inserts, that has long since gone!

The quality Swiss Lever Movement, winds well, runs strongly gaining about 8 mins per day

The Pocket Watch Case is in decent condition, GSTP S068212 and the War Office Broad Arrow is stamped on the Back, where there is some wear to the silver plate 

it measures 2.0 inches diameter excluding the Crown and Loop.