21" Hair Extension by Christie Brinkley instantly allows you to add length to your hair in just minutes. For longer, fuller, more beautiful hair, this one-piece hair extension clips in so easily. Its loose wave texture is designed to blend naturally with your own hair to provide maximum volume. The hair measures 21" in length and will easily turn any hairstyle into a beautiful, natural looking creation. This hair extension is made out of heat friendly synthetic fiber that can be styled with heat tools. The 21" Hair Extension is part of the Christie Brinkley Hair2Wear Collection.