Elgin Grade 317

The grade 317 is another 18 size movement, 15 jewels.

This example, made about 1921, is also in a swing-out case.

A swing-out case has a one piece back.  On most pocketwatch cases we see, the front bezel comes off, and the back comes off, and the movement is mounted in a third part, a sort of ring, in the middle between the two.

With a swing-out case, the front bezel comes off, and the movement swings out mounted on a hinged ring.

Swing-out cases are considered safer for the watches, since there is no gap at the back where a case back attaches.  There is that much less opportunity for dust and moisture to get inside.

There are a couple of variations of swing-out cases, but these examples I have been posted lately are typical.

JS033