sleepingdancer
·Sorry that I am a bit late to the party...
Your watch is perfectly fine with an original dial and a clean looking movement which is a cal. 30 T2
Case is a special construction to prevent intrusion of dust and sweat.
There are no case screws required nor a movement spacer ring with flaps as the movement sits snugly in the case back.
This is not a common snap back but is like a (deeper than a regular case back) "container" which is deep enough to embrace the whole movement and precisely slips into the upper case part and is friction held. A good first attempt to protect the movement - much better than a regular snap back.
If I were you I would not bother that you can´t find information about this particular reference - all you need to know is there and clearly visible... or would you like to know production numbers - this is (likely) impossible to find out unless you have access to the holy inards of the Omega archives...
I have searched my photo archive but have not been able to find a ref 2190 as most of my "entries" of references are from a 1948 catalogue and younger and not all references produced are shown in those catalogues.
The fact that you can´t find information about the reference does not inevitably mean it is a super rare one - there have been too many references back then to keep track on all of them. And as these are quite old watches (75-80 years) there will not be too many survivors of every reference.
And a rarely found reference does not mean high collectibility or value unless it is a 30 Rg chronometer built in few examples only.
There are other imporant factors for value for these watches with common ordinary movements like design, preservation, originality of parts and (sadly) the size.
best
Erich
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