Currently working and was tested over a 16 hour period and gained approx 1 minute. It will need a service to keep perfect time and is sold as is. The base metal case is 50.9mm in diameter. 1916 Hamilton, Grade 992, Model 2, 21J, 16S, lever set, stem wind, railroad grade, 5 adjusts, gold screw setting, double roller, double sunken dial with date serial number 1210269. Very nice dial, great case. A good honest pocket watch.