GHK Cu (copper peptide) used topically is one of the most well studied skin repair peptides. Here's how it helps the skin, in practical terms: 1. Boosts collagen & elastin GHK Cu signals your skin 2 weeks in on GHK Cu and the glow is REAL. Brighter complexion More even skin tone Less breakouts Softer fine lines Thicker, fuller hair This is just GHK Cu Powder Bulk Supply Shanxi Saien Biotechnology Co., Ltd Intermediate Cu(II) Thiolate Species in the Reduction of Cu(II)GHK by Glutathione: A Handy Chelate for Biological Cu(II) Reduction Inorganic Chemistry Does GHK Cu Really Work? 40 Years of Research Reviewed