A closeup of the "air" side of the membrane. Just like Ted said, there are no holes/slits in the center. Also notice the distinct "ring" in the center of the material, caused by the membrane settling down over the orifice, pushed against the opening by the water pressure bearing down on it, and effectively sealing it off...preventing water from entering the air supply line.

Did I get that right?



"Forget pounds and ounces, I'm figuring displacement!"

If we accept that: MBG(+)FGSF(=)HBG(F1)
And we surmise that: BG(>)HBG(F1) while GSF(<)HBG(F1)
Would it hold true that: HBG(F1)(+)AM500(x)q.d.(=)1.5lbGRWT?
PB answer: It depends.