19 CFR § 148.115 - Release of shipment.
(a) Release after examination. Unaccompanied tourist shipments:
(2) For which entry is made under the flat rate of duty provisions of subheading 9816.00.40, HTSUS, or under those provisions in conjunction with the regular rate of duty provision of another subheading of the tariff schedule, shall be released if:
(iii) The declared value conforms to the fair retail value in the country of acquisition, and
(d) Restricted or prohibited shipments. No shipment containing prohibited or restricted merchandise for which exemption is claimed under subheading 9804.00.70, HTSUS, or for which entry is claimed under subheading 9816.00.40, HTSUS, shall be released except upon compliance with the provisions of part 12 and §§ 145.51 through 145.59 of this chapter, and other applicable laws and regulations.
(e) Verification of claim. The port director may withhold release of any shipment for which exemption is claimed under subheading 9804.00.70, HTSUS, or for which entry is claimed under subheading 9816.00.40, HTSUS, to verify the validity of the claim. If he is unable to verify the claim, the merchandise shall be released under the provisions of part 141 or 145 of this chapter.