If you like tiny heat pipes, Note7 has you covered. This looks like the same "liquid cooling" copper heat dispersal apparatus we pulled from the vanilla S7 and S7 Edge.

Nearby, a note-able amount of glue secures this plastic cover over the S Pen chamber. It's probably there to help ingress-proof the stylus' slot.

Inside, a simple clip grabs the S Pen notches, and a gray rubber bumper protects the nib.