A metal plate bolted to the lugs of a fairlead to close the gap between them when there is any risk of a hawser or warp jumping out. This could occur, for example, when a ship is secured alongside a high quay and the hawser comes down through the fairlead at a steep angle. It originated in the Panama Canal where ships have to secure to the sides of the many locks at constantly varying heights as the level of the water is raised or lowered.
Panama plate on fairlead
Subjects: Maritime History.