It sounds like this thread is about those brands who have created a specific item that has achieved iconic "I know what that is" status - either they did it first or created a clever twist or simply make a particularly good or pretty version of a staple. Whatever, their brand name is indelibly popularly associated with the item, much like Hoover vacuums or Kleenex tissues.
In that category I would include:
Hermes "scarf" ties
Loro Piana Horsey; maybe Roadster too.
Aquascutum and Burberry trenches
Ralph Lauren Polos
That list is just off the top of my head, but in a way, that's probably a useful litmus test. I'm not endorsing all those items by the way (though most are excellent), just listing icons.