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A hair dryer diffuser can be either a specially designed hair dyer or an attachment that connects to the nozzle of a regular blow dryer. As an attachment, a diffuser can be sold separately or in combination with a traditional blow dryer. Diffusers are designed to evenly and gently distribute heat from the dryer to help minimize dryness, frizz and damage. This is similar in concept to the helmet-style hairdryers used in professional hair salons.
Diffusers are often used on curly hair, which tends to have less moisture than straight hair. A diffuser gently dries hair while preserving waves or curls. In contrast, regular hair dryers work by delivering a strong blast of warm air to the hair. This tends to straighten hair and blow out any natural curls or waves. Excessive heat from a traditional blow dryer also can dry out hair and damage it.
A diffuser can be used on straight hair. It can help tame fly-away ends and make hair look smoother. When aimed at the roots of the hair, a diffuser also can add lift and volume to straight hair.
The most common kinds of hair dryer diffuser attachments come in three forms. One is a circular attachment that has prongs or “fingers” at the end. These prongs can be either flexible or stationary. The prongs help to lift the hair and give it volume while it is drying. They can also be used to slightly massage the scalp as the hair is drying.
Some diffusers are designed to be adjusted in size or circumference. An adjustable diffuser allows either small or large sections of hair to be dried at one time. This kind of hair dryer diffuser works well on curly hair, because it allows more control.
Another type of diffuser is a flexible material that stretches over the hair dryer nozzle. It operates on the same principle as other diffusers but offers less control. An advantage to this kind of diffuser is that it is less bulky and easier to pack when traveling.
Hair dryer diffusers can be found in chain department stores and through beauty supply stores. When bought separately, care should be taken to ensure the chosen hair dryer diffuser will fit the hair dryer. Some universal hair dryer diffusers are available. Newer brands of hair dryers tend to have varying nozzle shapes, however, and not all diffusers will fit all hairdryers.
Some hair dryers are designed with built-in diffusers rather than attachments. This kind of hair dryer diffuser usually has a wide circular end instead of a pointed nozzle tip. Generally, they are less common than diffusers that are sold or used with traditional blow dryers.