Which of the following is NOT a type of sheet metal panel?

Flat metal panels are generally used as a structural or architectural surface but do not fall under the typical classifications of sheet metal roofing panels used in applications like roofing or siding. The other options represent specific types of sheet metal panels designed for particular functionalities: 5-V panels are characterized by their distinctive V-shaped ridges that encourage water runoff, corrugated metal roofing panels have a series of ridges and valleys to increase strength and durability, and double rib metal roofing panels are designed for enhanced load capacity and wind resistance. Each of these options is specifically intended for use in roofing applications, while flat metal panels are more versatile in use but do not serve a defined purpose as a structural panel in the same way as the others.