I need options on a watch that I bought recently. It has a 992b that matches the date on the case. Case back is marked K134581. Case body has the #'s 4781. What is the chance a mismatch at the factory. Than some watch maker. switching out the case back or body.

Here is the body #.

Here is the Movement.

Here is a photo of the shouldered Model a case. It has a ring of brassing.

Eugene. Th farther I go in this hobby the less fascination I have with who goes with what. Unless you followed that watch around for the last 70 years how would anyone know what has happened.

After all Hamilton made millions of these thing. You might say that I become am an agnostic purist.

Wow! Did I just make that up.

Haha, good one Phil.

You're right, all we can do now is notice that the numbers don't match and we don't know why.