Tripeptide-9 Citrulline is a cosmetic ingredient with various skin care properties, used in beauty products for its multiple benefits, including anti-wrinkle, anti-aging, skin repair, skin conditioning, antibacterial, and enhancing skin resistance. In terms of skin tightening, Tripeptide-9 Citrulline helps improve skin elasticity and firmness by promoting the production of collagen. Additionally, as a peptide, it aids in skin renewal and moisture retention, which contributes to a more tightened skin sensation. Citrulline, an amino acid with antioxidant properties, plays a role in promoting blood circulation and vascular health, which may indirectly help improve the overall health and appearance of the skin. Therefore, Tripeptide-9 Citrulline combines the dual benefits of skin tightening and antioxidant effects, making it a valuable component in skincare products.