Toppik Hair Building Fibers are made of keratin protein fibers that electrostatically cling to existing hair to instantly conceal thinning areas, receding hairlines, and sparse spots. They blend naturally with your own hair color, creating the appearance of thicker, fuller hair in seconds. These fibers are lightweight and resistant to wind and transfer, offering a reliable solution for achieving a more confident look throughout the day. They are suitable for both men and women seeking an immediate cosmetic enhancement for thinning hair.