Thought I might try to get the opinions of the collective here... I have a clamshell chronograph, but this is one that does not have the screws to hold it together unlike the Gallet/etc type of clamshells. Any thoughts on what might hold this case together? I was thinking the crystal, but not sure I can figure out how it works.
I suspect that the caseback/case is a single piece that goes in the case ring/lug assembly in the same manner as one of the Seamaster Cosmic 2000 series. The movement is put in through the front and the crystal and O ring hold it all in place. Then the "tuna can" is pushed into the caseband and retained by another O ring.