What Does That Thing Do: Lightning Arresters

What does that thing do? It's a lightning arrester.

https://video.wixstatic.com/video/f84a5d_7565b05a568b4da0b09cb5cc0c3c99ee/1080p/mp4/file.mp4

Lightning arresters divert lightning away from the electrical power supply and to the ground.

Lightning can hold up to 300,000 volts of electricity, but your home can accept a maximum of only 240 volts — more than 1,000 times less. Without lightning arresters, your home, and the power supply itself, would be far less safe.

Now you know what that thing does!