[Test-Equipment] customs duty on test equipment shipped Canada -> US

[David DiGiacomo]

Is customs duty is charged on test equipment purchased from a Canadian
dealer and shipped to the US?

Should the declaration be filled out in a particular way?

If the equipment was made in the US and exported to Canada in the first
place, it should be duty free, right?

I tried to find this information on the web, but got completely lost.

Private responses are fine... I can summarize to the list if there is
interest.

Thanks,

David DiGiacomo