The Secret Your Skin Already Knows GHK Cu is not a random combination of letters. It is a naturally occurring copper peptide that helps your skin do what it already knows how Squalane + Copper Peptide (GHK Cu) Rapid Plumping Serum Jumbo Size Advanced Copper Peptide Hair Regrowth Formula GHK CU & AHK CU, Copper Peptide Hair Growth Treatment Serum For Men Women Walmart.ca Two Ingredients. Real Hair Transformations. How Neurogan Health's GHK Cu Serum Is Changing What Customers Expect From Hair Care