The service-entrance cable SEC (blue arrow) is a line of service conductors (white arrows) located between the terminals of the service equipment (main disconnect) and a point usually outside the building, clear of building walls, where they are joined by a tap or splice (orange arrows) to the service drop or overhead service conductors (red arrows).

Valleys are weak spots in roofing systems. They have a lesser slope than the adjacent roof planes. They erode faster because water is directed into them. Inspectors must look not only at visible flashing, but also at the adjacent roof covering, at least a couple of feet on either side.