It wraps the content keys with a standard pub/priv algo then wraps that in a post quantum algo.

post quantum being an alog which we believe to be resilient in the face of emerging quantum computers.

The wrapping is done because the post quantum algos are new and might be flawed, so if that is broken (and we aren't post quantum) then the standard algo will still protect the content.

NIST recommend the use of these hybrid keys:

https://csrc.nist.gov/pubs/ir/8547/ipd

Delicious bull-shit bingo dressing? A bit like Thousand Islands dressing but for code.

Here's an explanation of what it is supposed to be:

https://quantumsecuritydefence.com/quantum-news/hybrid-pqc-c...