Surge Suppressor?

[Mark R. Long]

I know that similar questions have been asked before, but is this round gray plastic device that's attached to the side of the service panel, a surge suppressor? It was double tapped at the entrance cable terminals.

[Ted Allen]

here

Better

I do believe they should be mounted outside the box (as your pic shows) instead of inside the box as shown in the link.

[Greg Fretwell]

They should be connected to a load side breaker, not the service conductors.

[Mark R. Long]

Thanks for the info, Greg and Todd!