This dryer attachment is one of the most popular attachments as its main purpose is to add volume and define curls without frizzing up hair. It allows your hair dryer to give a softer blast of air instead of blowing your hair all over the place like a hair dryer will do with out an attachment.
A diffuser is best used on a lower heat setting, and although it makes for a bit of a slower process the end results can be very rewarding. A more defined curl, less frizz and softer looking curls or waves. The fingers on the diffuser work to help separate the hairs from each other for a fuller more voluminous effect.