The appearance of bald spot and thin hair instantly becomes better with Caboki Black Hair Building Fibers. These hair fibers can be used to cover up part lines and bald spots, and blend in hair extension lines into the original hair. The micro fibers creates a firm bond with the hair, making them look thicker than before. They become unnoticeable once they blend in. These fibers are resistant to water, sweat and wind. This product is ideal for men and women both.