The Peptide Craze Ground Truths Holly What you NEED to know about GHK Cu peptide and X39 by Jen O'Sullivan of www.PatchEDU.com Here's the real difference, and it's simpler than people make it. Your body already knows 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 Therapy: The Definitive Clinical Guide to Gene Modulation, Protocols, and Efficacy