The meaning behind those colorful balls on power lines

What purpose of Those colorful balls attached to Power Lines?

Transmission tower - Wikipedia

What are those colorful balls really for?, Local News

What Are Those Balls That Hang On Power Lines?

Why Can't Texas Just Bury Its Electrical Lines? – Texas Monthly

Transmission tower - Wikipedia

What's With The Orange Balls That Hang From Power Lines In Colorado's Canyons?

Why Can't Texas Just Bury Its Electrical Lines? – Texas Monthly

What Are Those Colorful Balls on Power Lines, Exactly?