(a) For vessels other than those covered in paragraphs (b) and (c) of this section, the name of the vessel must be marked on some clearly visible exterior part of the port and starboard bow and the stern of the vessel. The hailing port of the vessel must be marked on some clearly visible exterior part of the stern of the vessel.

(b) Vessels with square bow. For vessels having a square bow, the name of the vessel must be marked on some clearly visible exterior part of the bow in a manner to avoid obliteration. The name and hailing port must be marked on some clearly visible exterior part of the stern.

(c) Recreational vessels. For vessels documented exclusively for recreation, the name and hailing port must be marked together on some clearly visible exterior part of the hull.

(d) The markings required by paragraphs (a), (b), and (c) of this section, which may be made by the use of any means and materials which result in durable markings, must be made in clearly legible letters of the Latin alphabet or Arabic or Roman numerals not less than four inches in height.