Patek Philippe

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for pocket watches 980 and 983 Very nice indeed.

it is cal. 17" SAV PS :-) Oliver

It's a 17''' SAV (savonette) PS (petite seconde) caliber Has already been said the pocket watches which houses this caliber.. If you want to find the same antique and traditional design in a PP wrist movement, you have to look the 12-120 caliber... I thin...  

albeit with improved performance (e.g. 7 day power reserve) and from an unexpected source (image: Franck Muller): Best, Magnus ...