Currently working and was tested over a 15 hour period and gained 10 to 20 seconds. It may need a service to keep absolute perfect time. 1913 Hamilton, Grade 992, Model 1, 21J, 16S, stem set, stem wind, 5 adjusts, double roller, gold screw setting, double sunken dial with date serial number 1019245. The gold plated case is 49.1mm in diameter. Dial has a very tiny crack between 11 & 12, nice case.