Copper Peptide (GHK CU) Serum Dermaesthetics For Professionals Copper Peptide 10% GHK CU, 5% AHK CU with Oligopeptide 1 Hair Treatment Serum eBay A lot of people asked how I use GHK Cu (copper peptide) with a pen device, so here's a quick tutorial showing exactly how I do it. In this video I show how GHK Cu Peptide Serum 30 ml, Copper Peptide Serum with Hyaluronic Acid for Tightening, Collagen Boosting Revitalize Your Skin: The Benefits of Copper Peptide for Youthful Glow