The movement is typically a ladies watch. It was however used in a number of smaller gent's watches with larger dials. Usually square or rectangular. These are now refered to as unisex watches as they are often less than 30mm.
This is actually a great movement, about 18mm. Usually one finds the 681 which have date or the 620 which does not have a sweep. The build quality is similar to the 55x series. The bridges stack making the movement a lot thicker.
Not the smallest automatic. There are a few smaller 660 comes to mind.
As usual cases for these can be hard to come by. Many were scrapped for the gold content. A lot of ladies watches were gifted and worn only once. Styles changed quickly.
