In 1939 the British Ministry Of Defence ordered some 133,000 Military Watches from 16 different Swiss Watch Companies these ATP ( Army Trade Pattern ) watches which pre dated the Dirty Dozen went through the war and a lot met their demise during the war, or been decommissioned after it, those remaining are getting rarer.
 
This Timor is in very good condition for its age, the case is chrome plated with a steel screw back. The movement is a 99B Timor based on a Peseux 190. The watch has just been serviced and a new balance staff and mainspring replaced. It is now working very well. 
We date this to circa 1940/1