GHK Cu: The Peptide That Transforms Skin and Tissue Health Calibrate Hydration GHK Cu Copper Peptide Serum 1% Conc. Hair and Skin Boost Collagen *BEST VALUE! eBay Australia Not all Copper Peptides are created equal If you've tried copper peptides before and saw no change, here is why: Concentration and Stability. Most serums use a diluted solution that barely scratches 7% GHK Cu Cosmetic Ingredient Accelerant Skin Biology 15 ml