Cu Peptide Before and After: What to Expect for Skin and Hair How long does GHK CU take to start working? #ghkcu #transformation #ghk #skin #mt2 GHK Cu is one of the most talked about peptides in aesthetics right now. But how much of what you have heard about it is actually true?, Copper peptide, known as GHK Cu, has a growing body of peer GHK Cu Peptide for Skin & Hair Facial Serum & Scalp Solution