Isolated danger marks indicate an isolated danger which may be passed on all sides. As these marks are erected or moored on or near dangers, they should not be approached closely without special caution. These marks are colored black with one or more broad horizontal red bands and are equipped with a topmark of two black spheres, one above the other.
[CGD 86-031, 52 FR 42640, Nov. 6, 1987, as amended by CGD 88-018, 54 FR 48608, Nov. 24, 1989]