The class 3 hull reinforcement in live build has 50% caustic protection.
It already had this in beta build, but no Thargoids were enabled for testing.
Installing 2 of these modules give 60% caustic protection in total, so installing at least one is probably the most efficient. It should double the survival time against the Thargoids, if they are really doing caustic damage.
Probably the module being in game in its current form is a bug, as only the class 3 hull reinforcement seems to give caustic protection.
It already had this in beta build, but no Thargoids were enabled for testing.
Installing 2 of these modules give 60% caustic protection in total, so installing at least one is probably the most efficient. It should double the survival time against the Thargoids, if they are really doing caustic damage.
Probably the module being in game in its current form is a bug, as only the class 3 hull reinforcement seems to give caustic protection.