Maritime Navigation Rules Exam Prep 2026 – Complete Practice Test

In daylight, day shapes tell other mariners about what your vessel is doing. A vessel that is being towed is indicated by displaying a diamond shape. This marker is the standard sign that shows you are not the leading part of the movement but are being towed behind another vessel. The fact that the tow length exceeds 200 meters doesn’t change the basic identifying signal for the towed vessel—the diamond is still used to communicate that status. The other shapes—ball, circle, square—are associated with different conditions or purposes and don’t convey “being towed” in the same way.