Omega

Spring driven with lever escapement. Manual winding.
Round silver case with double cover that opens as a pocket watch. White enamel dial with large hour marks filled with luminescent colour (originally lightgreen, today brown). Hands are of the same color. At 6 o'clock small second dial. On the case rim at 6 and 12 o'clock position wire strap fasteners.
These kind of wrist watches with large, fluorescent numerals were used for military purposes. Sometimes they had a grid cover that protected the dial and allowed one to read the time.
In the chapter Production Numbers and Dates of the book Warman's Watches Field Guide[1] is written that Omega watches had numbers between 4,000.000 and 5,000.000 date from 1910 to 1915, and between 5,000.000 and 6,000.000 date from 1915 to 1920. In the book Complete Price Guide to Watches[2] is written that housings had numbers from 5.000.000 to 6.000.000 between 1913 and 1918, and movements 4,000.000 in 1910., 5,000.000 in 1915. According to the number of the movement – 4790060, and housing – 5550594, this watch can be dated to 1914 – 1915.
[1] Judy, Dean. Warman's Watches Field Guide : Values and Identification. Iola : Krause Publications, 2005., str. 510
[2] Complete Price Guide to Watches. Mount Pleasant : Tinderbox Press, no. 29, 2009.