Feather Hair Extension Clip In, Assorted Colors, Three 12" Hair Extension by HairExt. $10.99. Clip-In Synthetic Hair Extension. Pattern and Color May Vary. Length: 12". This 12" Clip-In Hair extension allows you to add fashionable style and color to your hair. Affordable, lightweight and easy to attach, these extensions cab be put in and taken out in a matter of minutes.