i would not recommend immersing the watch with the module in it. if it leaks {and it probably will} you have just ruined your watch. before immersing any watch,especially, one that is only rated water resistant, you should have it pressure tested for leaks. older watches WILL leak at the crystal, buttons, case back, and crown if one is present. the gaskets for the most part have lost their resilience and are hard and brittle. just my 2cents. you will be sorry.

. peter