Rivaj Hair Building Fibers 25g – Black Instant Hair Thickening SolutionHair Building Fibers 25g Black Hair Building Fibers 25g Black is the perfect solution for instantly achieving the appearance of fuller, thicker hair. Specially formulated with natural keratin protein fibers, these micro sized particles bond to your existing hair through static electricity, creating a natural, undetectable finish. The deep black color blends flawlessly with your hair, ensuring no visible lines or patches. Whether you have thinning