Hair Building Fibers, made of colored keratin protein, blend undetectably with existing hair strands to instantly create the appearance of naturally thick, full hair. It resists wind, rain, and perspiration for long-lasting results in all conditions. It's also one of the professional industry's secrets to making actors look their best on camera! Available in nine shades that can also be mixed to match virtually any hair color. Hair Fibers work for all hair types and textures and are also great for part lines, covering extension tracks, and root touch-ups between hair color appointments. Easily washes out with shampoo.