Copper Peptides for Skin: What GHK Cu Does and How It Compares to Retinol One of my personal favorite peptides: GHK Cu (Copper Peptide) I've been using this one consistently and I absolutely love what it does for skin health, healing, and overall cellular repair. GHK Cu is Skin Perfection GHK Cu Copper Peptide Serum Booster, 1 Percent Blue Liquid For Face, Neck, Body, Hair, And Scalp, 0.5 oz Walmart.com GHK CU Warrior Peptides