This is a rubbery helmet that a person wears while participating in the sexual activity of 'scat' (poo sex). It is used to prevent poo from getting to ones hair, as poo is quite hard to wash out of hair.
Dude man i have to take a shit let's do some scat! OMFG HOLD IT IN MAN LET ME GET MY SCAT HELMET FIRST I'VE JUST HAD A SHOWER!
by lolerface August 07, 2006