John asks:

What is a skull?

Hard bony thing, usually surrounding a brain, with various openings for sight,
sound, aspiration and other uses. ;-)

Or, with a "C" in stead of a "K", it sounds like an oar. But I have to admit
to being as mystified as you.

Of course, he could mean "hulls", in which case he's looking for the
"TriFoiler" from Hobie.

http://www.hobiecat.com/sailing/models_trifoiler.html

Steve