u/Mysterious_Tough4539

Trying to open the case back on a vintage Spartan Time pendant/fob watch I picked up for a fiver at a vintage store to access the movement. I've checked around the entire seam and can't find a notch or indentation to pry with a case knife.

No visible knurling either, so not sure if it's screw-back, snap-back with a worn/hidden notch, or opens from the front bezel instead.

Photos attached of the case back and front. Any idea how this one opens, or what I should check for?

I'm not a pro at any of this so any help will be appreciated

Thanks!