My '82 Precista has a 21J ETA 2783 which lead me to think that this was the standard movement for the watch. After some recent MWR traffic on the subject I can say that the 2783 25J was probably more widely used. Of six auto movement images I have seen, 4 are 25J and 2 are 21J. It could be that the 21J was a replacement movement introduced during the watches service life or that when Gallet/Racine built the watches they used a mixture of 21J and 25J movements. Either way MOD DefStan states a minimum of 17J for the auto diver's so MOD would not care if they were 21J or 25J. The rotor in the 25J is decorated in a honeycomb style whilst the 21J rotor is plain.

If anyone would like to confirm the movement fitted in their watch please forward details.


Terry Andrews