I was watching this video of a GMT being refinished (https://youtu.be/t_TzuyHdb64) - and noticed in the shot at 20:38, the case has some kind of pink protective layer that was applied. It doesn’t look like polyamide tape, but rather like some kind of gel that’s painted on and then later removed chemically? Or am I totally making that up and it’s actually just a layer of tape that’s been partially worn away?
Here’s a screenshot:
Here’s a screenshot: