Originally posted by westcoaststyle
It is a little confusing, but it makes sense to me.
well, put a straw half submerged in a cup of water and suck as hard as possible without fully submergine the straw, chances are you will never get any fluid.
or heres a godo example of that breather valve. take a straw and poke holes all over half way up, submerge it completely at the bottom and suck hard. even the milwaukee brewers dont suck hard enough to get fluid up that straw.