Unfortunately, none of them was really tight when I filled carbonated beverages (soda or apple juice).
In upright stored state and without a lot of shaking everything was always super (so had to stand overnight for testing in the kitchen), but once they are shaken times in his pocket and eventually fall over (eg school bags), they drop out.
Since this was in all four cylinders so, I do not think this is just about a mounting production.
Nevertheless, we are happy to take them on, just stop without bubble :-)
