Does anyone know whether there is an atelier / specialist / subcontractor who makes rubber straps for brands or do most brands actually manufacture their rubber straps in-house (i.e. is there a company to rubber straps like what Vaucher or Frédéric Piguet is to movements?). For example, does PP have a rubber factory for the aquanaut straps? And what about smaller brands like the rubber straps used by Czapek?
Bonetto Cinturini is rumored to be the biggest https://www.bonettocinturini.it/en/company https://www.bonettocinturini.it/en/home