I'm such a doofus that I can't even spell "doofus" correctly. I spell it "doffus," which doesn't even make sense since it's pronounced "doo fuss." At least if I'd spelled it "doofuss" I'd have had an excuse.
A modified down tube for a water pipe that instead of just having one large hole opening into the water, instead the glass comes to a closed tip, along which are several smaller holes. This supposedly cools the smoke before being inhaled by diffusing (spreading) the smoke over a larger area.
Fuck, smashed my down tubecleaning it. Replaced it with a diffuser instead so my smoke should be cooler.