You can still "fiddle with your thingy" - it's just a method of forcing juice into the carto, AFTER it's in the tank of juice...using air pressure from closing the thingy.
The Slap Yo Mama isn't hollow. It's just solid metal.
And flanged cartos can't be changed like the unflanged ones. I have several of both types so different ways for whichever I end up locating in this pile of chaos my room is in its current state....lol
Ugh, I need sleep. Someone tell me why I'm still awake? LOL