Signal Flag Letter "P" 3' X 3' (#7) w/toggles

In harbor: "All persons should report on board as the vessel is about to proceed to sea."
At sea: It may be used by a fishing vessel to mean: "My nets have come upon an obstruction."

In harbor: "All persons should report on board as the vessel is about to proceed to sea."
At sea: It may be used by a fishing vessel to mean: "My nets have come upon an obstruction."

The International Code of Signals is an international system of signals and codes for use by vessels to communicate important messages regarding safety of navigation and related matters. Signals can be sent by flaghoist, signal lamp, flag semaphore, radiotelegraphy, and radiotelephony.

A complete set of code flags consist of 40 flags: 26 alphabetics, 11 numeric and procedural  pennants, and 3 substitutes.

To make full use of the system, the book Pub102 International Code of Signals is recommended.  See in Professional/Bridge.