Cal 492 for vintage chrono

I looked for the history or some information/details in VC books about this caliber, but unfortunately cannot find any...
I would like to know when it was launched and for which kind of chronographs (references). Did it come from JLC?
I join a photograph of it (I think it's the right one) to know your mind about it.
Quality? Comparison with the 434?



Thank you for all coming info.
Cheers, Patrice
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