Stimulates Hair Growth & Improves Hair Quality: Redensyl serum for hair stimulates capillaries, thus helping to improve the blood supply to the scalp. This accelerates the renewal of cells and strengthens hair roots so that they are not pulled out easily. Hibiscus extract in saturn hair serum is rich in vitamin C and other antioxidants that help to repair and restore the hair follicle. It also protects against bacteria which can cause scalp infections.