What are end papers used for in perming?

End papers serve a crucial role in the perming process, specifically to provide a better curl structure and protect the hair ends. They are thin pieces of paper that wrap around the hair during the perming procedure. By using end papers, the stylist can ensure that the ends of the hair are properly wrapped around the perm rod. This technique helps to create uniformity in the curl pattern and prevents the hair from becoming frizzy or damaged at the ends, which can occur if the ends are improperly processed.

The reason the other options do not apply is that end papers are not primarily used to protect the scalp from chemicals; that is typically the role of a scalp protector or barrier. They do not measure hair length, as this is done using a measuring tool or ruler. Additionally, end papers do not color the ends of the hair; their function is limited to assisting in the curling process rather than altering hair color. Thus, the use of end papers directly contributes to achieving optimal results in perming by enhancing curl quality and protecting the hair.