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I have no idea what the guy means by "(t)wo SNs on bills!", nor do I care; but I will observe that all US currency has borne two serial numbers for many years In the case of the most recent issues, the serial numbers have consisted of two letters, eight numbers and a letter. The first and last letters, and the numbers, are completely random; and the second letter matches that of the issuing bank. For example, the Federal Reserve Bank of Boston is indicated by the letter "A" and the number "1" (see below the serial number at upper left), so that a FRN distributed through it might be, for example, GA38563857R. One issued by the Dallas FRB might be FK18376937H, and one from New York might be HB17272004R.***** wrote:Two SNs on bills!
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