GHK CU (50mg) Nordsci Should Bodybuilders Take GHK Cu? Neurogan Health 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 Let's face the facts: Tighten Plus is pretty tight! Designed with GHK Copper that may smooth out wrinkles, repair and tighten skin, and fight inflammation, this facial cream packs an age managing