Peptide Injections: What They Are, What They Promise, and the Big Unknowns 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 Copper Peptides vs. Retinol: Which Anti Aging Powerhouse is Right for Pure & Cimple Injectable GHK Cu: Beginner's Guide to Copper Peptide GHK Cu Simon's Compounding Before vs. after 3 months of GHK Cu peptide therapy smoother texture, more even tone, and skin that looks healthier overall. Small peptide, big difference