GHK cu is a copper peptide. It's great for skin, especially when you combine it with other things. My favorite is DMSO and derma rolling. My first experience with copper peptides was Procytes GHK Cu (Copper Peptide) 50mg 99.80% Purity Research Peptide Miro Biotech Dimeric copper peptide incorporated hydrogel for promoting diabetic wound healing Nature Communications Revitalize Your Skin: The Benefits of Copper Peptide for Youthful Glow GHK cu is a copper peptide. It's great for skin, especially when you combine it with other things. My favorite is DMSO and derma rolling. My first experience with copper peptides was Procytes