it depends on juice viscosity, additional holes can be plugged up using a pressed tip mesh which allows air flow at the same time prevent massive leakage.
Till date on mesh there is no 100% leak proof. Mesh is meant to wick liquid for you. tilting it upside down will still cause leakage. its just a matter of how much liquid is leaking out.
make sense?
You zhun bo there is no 100% leak free meh
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