Again one of a few American watch of the collection (altough made in Switzerland CH :)). This is a vintage lady mechanical watch of 17mm with a Buren 86 caliber of 17 jewels. This is so far the smallest / tiniest watch I saw and I tried to repair (see pictures the movement is 13mm...).
Info about the specs of the Hamilton - Buren Cal. 86; here.
If you want to read more about the history of Hamilton; here.
If you want to read more about the history of Buren; here.