I am a new member,
You’ll need to post some pics mate, several of these DeVilles dont even have a back that comes off, they’re front-loading watches that need a special tool and a watchmaker’s expertise to take apart.
Well, ah, what were your intentions if and when you get the case back off, or otherwise the crystal, bezel, stem and stud off, the then find out how to get the movement out of the case? If it is your watch, gung ho! But if it isn’t your watch, you need to think about what you are trying to do.
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