50 CFR § 660.704 - Vessel identification.
(a) Applicability. This section only applies to commercial fishing vessels that fish for HMS off, or land HMS in the States of California, Oregon, and Washington. This section does not apply to recreational charter vessels that fish for HMS off or land HMS in the States of California, Oregon, and Washington. Each fishing vessel must be marked for identification purposes, as follows:
(ii) The vessel's official number must be affixed to the port and starboard sides of the deckhouse or hull, and on an appropriate weather deck so as to be visible from enforcement vessels and aircraft. The official number must be affixed to each vessel subject to this section in block Arabic numerals at least 10 inches (25.40 cm) in height for vessels more than 25 ft (7.62 m) but equal to or less than 65 ft (19.81 m) in length; and 18 inches (45.72 cm) in height for vessels longer than 65 ft (19.81 m) in length. Markings must be legible and of a color that contrasts with the background.
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