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A bright white light visible from all directions, placed at a height of at least 5 m. This height may be reduced to 4 m for vessels whose length does not exceed 40 m;

By day:

A yellow ball in a suitable position and high enough to be visible from all directions.

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However, if the convoy ends with a row of more than two vessels coupled side-by-side, only the two outside vessels of the row shall carry such lights. If the rear of the convoy is made up of small craft, those craft shall not be taken into account for the provisions of this paragraph.

5. When passing through the opening of a fixed or closed bridge or weir, or when passing through locks, the vessels of a towed convoy may carry the lights prescribed in paragraphs 1(a), 2 and 3 of this article at a reduced height so that passage may be effected without difficulty. 6. Where the vessels referred to in paragraph 3 above are seagoing vessels coming directly from or leaving for the sea, they may carry:

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Instead of the white light, the side lights prescribed in article 3.08,
paragraph 1 (b);

By day:

The yellow ball.

76. The provisions of this article shall not apply to small craft towing only other small craft or to the towing of small craft.

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