what are the balls in power lines for
Balisor High voltage power cables, particularly those close to airports, need to be visible day and night. During the day, brightly coloured balls positioned along the length of the cables are sufficient, but during the night, lighting is necessary. These beacons provide this lighting by glowing red, the standard colour used in aviation for warning beacons.
Cricket ball The nature of the cricket ball slightly varies with its manufacturer. White Kookaburra balls are used in one-day and Twenty20 international matches, while red Kookaburras are used in test matches played in most of the ten test-playing nations,[4] except for the West Indies and England, who use Dukes, and India, who use SG balls.[5]