Hamilton Military Pocket Watch Case with crystal and crown. This was used during the second world war so it is a little dirty and I have not cleaned it so left it just the way I found it in other parts I purchased in the 1980's from a watchmaker who retired. This is for 16 size watch and on the case back it says "AN 5740 Mfr' Part No. 4992B Serial no. AF-42-41155 Contract No. W535.ac-28072 Hamilton Watch Co.