The cups are molded very tough polycarbonate with glass fiber.
You can grab the cups and twist them, bending the metal prongs of the headspring to fit the tow-in/out angle to your head. Nothing will break.
Naked foam is there to let the sound escape the ear-chamber as fast as possible. Ribbon driver does not need sealing to create bass, so lots and lots of leakage was the goal. That allows for great dynamics and doesn’t pressurize the eardrums.
We are trying to get the best connection of ears and ribbon drivers to open space, not seal them. Makes the sound more natural for several reasons in our hearing mechanism. So, naked, open cell foam it is, sacrificing the appeal to it’s majesty The Sound.
Plus, they are washable (pressing in a water bath with a bit of dishwasher, do not twist or pull).