This article is about the international maritime signal flag representing the letter Z. For the microprocessor Z flag, see Zero flag. For the Russian military symbol, see Z (military symbol).
The Z flag is a diagonally quartered square consisting of four isosceles triangles with their apexes meeting in the center of the square – a yellow triangle on the top, blue at the fly (right), red on the bottom, black at the hoist (left). It is the only flag in the international maritime flag set to use four colors. In heraldry, it would be described as Per saltire or, sable, gules and azure
