Sorry to hear that mist, I was pretty surprised myself that it arrived here without any delays at customs.
But as Im waiting for my batts lets say we are in the same boat ;-)
Usually the Customs open and verify something like 25% of the ordinary packages. Only 1 over 4.
And if your package does not contain any sort of bill, it will necessarily be stopped because the customs would need to ask you about its price in order to calculate the taxes and duties. Especially when they do not have the slightest idea of what that is.
This is why I always ask my sellers to include inside
and outside the package, any kind of paper that looks like a bill, preferably under 50$, and to label them as "battery chargers" (for devices) and "electric resistance" (for atomizers) or "x flavor" (for e-
juice)...This is usually the best way for "no questions asked".
The reason is simple: An employee at the customs is an employee. When a package arrives, he has to fill a form. And in this form, there are categories...like "electrical", or "food", or "perfume", or "clothes", or "toys"..etc...etc...Then there are range prices. And whatever information he does not find stuck on the external package, makes him open up the package to see if it might be inside. And if inside he still does not find it, then there is a whole procedure that starts.
So the most important thing for a seller, if he cares for quick deliveries to his customers, is to avoid having the package opened up, at the first place.
Good and clean packing + external bill stuck on the exterior of the package, including clear identifiable fields and price range, are the best way for success.