Amazon.com: TOSOWOONG Copper Peptide Face Serum, Anti Aging with Copper Tripeptide, GHK Cu, 12 Multi Peptide Formula for Fine Lines, Firming, Skin Elasticity, Hydrating, Korean Skincare, 33ml 1.11 fl.oz. : Beauty & Personal Care What Is Peptide Therapy and Is It Safe? Uses and Benefits #ghk GHK Cu is a naturally occurring peptide in human plasma that declines with age. When used in injections (usually subcutaneous), it can offer various benefits: Skin Rejuvenation and Anti Aging: What Is GHK Cu? The Copper Peptide That Rejuvenates Skin