My understanding is that there wouldn't be one, as the card is a different document than a non-immigrant visa (though serves much the same purpose).
If you are answering this question on a form, I would answer "N/A - BCC."
My colleagues are accurate. The crossing card is a document taht is provided for entry purpsoes and would not have a visa number.
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I agree with my colleagues.
J Charles Ferrari Eng & Nishimura 213.622.2255 The statement above is general in nature and does not constitute legal advice, as not all the facts are known. You should retain an attorney to review all the facts specific to your case in order to receive advise specific to your case. The statement above does not create an attorney/client relationship.