Toppik Hair Building Fibers in Dark Brown are a revolutionary solution for thinning hair, instantly transforming the appearance of hair by creating a fuller, thicker look. These natural hair thickening fibers are made with high-grade keratin protein, the same protein found in real hair, ensuring a seamless blend for a natural finish. The fibers adhere to existing hair through static electricity, creating a bond that resists wind, rain, and perspiration. Toppik Hair Building Fibers are undetectable and suitable for all hair types, providing a boost of confidence with every application.