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 Copper tripeptide GHK CU Crepey Skin Escape Platinum Skin Care GHK CU for Sale Tripeptide 1 3rd Party Tested US Made GHK Cu 100mg Eden Scientific 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