Now introducing one of my favorite peptides.. GHK Cu This is a naturally occurring copper peptide your body already uses to repair and regenerate skin. As we age, those levels decline and that's Uncover the Power of GHK Cu peptide FIT9 After a year of using GHK Cu both topically and going deeper than topicals (under my doctor's care), the difference in my skin is not something I have to squint at in good Squalane + Copper Peptide (GHK Cu) Rapid Plumping Serum