What is an appropriate datatype for an RFID, and is there a standard definition for the format?

I have a database that tracks people based on RFID tags embedded in their shoes. This data arrives in a VARCHAR(MAX) column with other data mixed in, in no particular order. So far, all the RFID values are formatted like the following:

AnnnnnnnnAnnAAAA  (where A = 0-9  and n = A-Z)

I am writing a report to extract RFIDs from these messages and store them in their own table. As long as the RFIDs follow this same pattern, I can find them. If the RFID format changes, my extraction process will fail.

Is there a standard format for RFID tags? What datatype would be best suited to store RFID tags?

I am going with VARCHAR(20) for now.

I don't like answering my own questions (feels like cheating) but here goes:

According to a post on StackOverflow there is no fixed datasize. RFIDS can vary in both length and format, depending on the industry.

I will stick with varchar(20) for my own purposes, because the batch of RFIDS that we purchased all fall within that size limit.

StackExchange Database Administrators Q#15347, answer score: 6