Copper Peptide Hair Growth Serum (10% GHK Cu + 5% AHK Cu) 30ml ROBYN'S TACK ROOM GHK Cu Dosage and Protocol: A Medical Provider's Guide to the 30 Day Cycle Perfect B In Vitro and in Vivo Studies of pH Sensitive GHK Cu Incorporated Polyaspartic and Polyacrylic Acid Superabsorbent Polymer ACS Omega 12 weeks in, and my skin has NEVER looked better! GHK peptides are doing their thing. Alright, I need to give you an updateit's been 12 weeks since I started using GHK