Well thus far we have spotted about 15 different brands being used during spacewalks since 1965...
For the use of the Kapton foil, there're several reasons:
1. Extra attachment (added strength as the watch straps are not EVA-rated)
2. Thermal insulation against 200°C differences in shadow & full Sunlight
3. Static insulation against electrical fields associated with moving fast through low density atomic Oxygen.
4. Easier to spot both during and after the EVA as some of these were personal pieces. Most likely post-mission souvenirs to family !
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#MoonwatchUniverse
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