Sea pen

I have a bit of a cold at the moment.

There's lots of snot involved.

A colleague, hearing me sneeze for the umpteenth time, made a suggestion :
"Il te faut quelque chose pour décongestionner les sinus - style, eau de mer."
(You need something that'll unclog your sinuses - like, sea water.)

The only thing was that he said it really fast, so with my cotton-filled head what I HEARD was the following :
"Il te faut quelque chose pour décongestionner les sinus - stylo de mer."
(You need something that'll unclog your sinuses - sea pen).

Of course, I was all, "c'est quoi, un stylo de mer?" (What's a sea pen?)

Two days later and he's still asking me if the sea pen is working.