Omega Mens Constellation"Manhattan" 1991 - caseback screw or snap?

Posts
1
Likes
0
Hello All, as the header already mentions, I am trying to figure out whether the above watch has a screw back or snap back. I own the watch since 1991 and to identify the exact case number I want open its case back. There are no visible or tangible grooves that would allow for an opening blade. I have tried opening with a ball but to no avail.
I want to be sure what I am dealing with before I use somewhat more "pressure".

Thanks.
 
Posts
29,376
Likes
35,343
Most of these are press-in when they don’t have keying, best to let a watchmaker handle it though to prevent further scratches like those on the case-back