Originally Posted by
MoAlpha
The other type has a diaphragm with a "star" of slits in it, which opens under a pressure gradient. They also suck air and emit a strange, reedy, whine after you drink.
I've made the mistake before of placing one of those on my nightstand in case I wake up thirsty.
Instead I wake up to a disorienting but quiet "eeeeeeeeeeeee"