The Postmaster General may not make a rule that—
(1)
prohibits or materially impedes the mailing of firearms, ammunition, or any component thereof; or
(2)
requires, as a term of mailing a firearm, ammunition, or component thereof—
(A)
the disclosure of firearm, ammunition, or firearm or ammunition component sales receipts, firearms transaction records, or other customer records kept by Federal firearms licensees or ammunition sellers; or
(B)
the disclosure of the serial number of any firearm or component thereof contained in the mail.