As standard, there is nothing inside them - I know this because I've just rebuilt the interior of mine. I am pretty sure the ones in the back have "Bose" written on them, but can't remember for sure.
I am upgrading the fronts (set of Focal Access 6.5" components) and I am putting the tweeters in behind the Bose grilles.
Go to my GT for less than a grand thread - see the pic of all the bits on the lawn? Open the pic in paint, and zoom. You can't see "bose", but there is certainly silver writing.
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