Acetyl Tetrapeptide-11 ek synthetic peptide hai jo skin ko firm aur tight banane mein madad karta hai. Yeh syndecan-1 aur collagen-anchoring proteins ko activate karta hai jisse skin ki inner layer strong rehti hai. Leave-on formulations mein commonly use hota hai, especially anti-aging aur firming serums mein. Regular use se skin ka elasticity improve ho sakta hai aur skin more plump dikhai de sakti hai.