Overhead power line markers are high-visibility devices, such as spherical balls, flags, or spirals, installed on overhead transmission and distribution lines. Their primary purpose is to increase the visibility of power lines, which are often difficult to see from a distance. They are crucial for preventing collisions with low-flying aircraft (such as helicopters and agricultural planes) and protecting migratory birds. By making the lines more visible, they also enhance safety for ground-level activities involving tall machinery like cranes or construction equipment.