Which of the following is NOT an implement or material needed for extensions?

The hood dryer is not considered an essential implement or material needed specifically for the application or installation of hair extensions. Instead, it serves a different purpose primarily in drying hair and setting styles, especially after chemical processes like coloring or relaxing.

In contrast, tools such as a hackle are used for detangling and preparing extension fibers, and extension fibers themselves are the fundamental materials used to create the extensions. A drawing board, while not as commonly referenced, may also be linked to some methods of preparing and arranging hair for extensions. Therefore, among the options listed, the hood dryer does not directly pertain to the process of applying or managing hair extensions, making it the correct answer to identifying what is NOT essentially required.