Power Line Markers can be found in Power lines which are located near airports.
Power Line Markers are mounted by means of helicopter as the locations on the power lines are not accessible otherwise.
In order to make these Power Line Markers visible at night, reflector strips are sometimes attached to them. These reflective strips reflect light from low flying aircrafts and helicopters making the power lines visible even in the night.
Self Illuminating Power Line Markers are also available. These Power Line Markers generate power from the electrostatic field of the Power line and illuminate LEDs in the Markers making them visible in the night.
Power Line Markers are also necessary in areas where industrial cranes and other tall vehicles move. If the Power Lines are not clearly visible, there may accidents when these vehicles and equipment come in contact with the high voltage lines.
Special disc type markers are available which can be attached to these lines by means of insulated hot sticks.