Toppik Hair Building Fibers are meticulously crafted from keratin protein to seamlessly integrate with natural hair strands, instantly enhancing the appearance of thickness and fullness. These fibers work by filling in thinning areas, concealing hair loss, and adding volume to fine hair. They can also act as a root touch-up between colorings and are resistant to wind, rain, and sweat, ensuring long-lasting results in any conditions. Available in nine shades that can be blended to match any hair color, Hair Fibers are suitable for all hair types and textures, including covering extension tracks and touching up roots between salon visits. Easily washed out with shampoo, Toppik Hair Building Fibers are a simple and effective solution for achieving instantly fuller hair for both men and women.