Peptide Labz Copper Peptide Hair Growth Serum, 10% GHK cu, 5% AHK cu, Rejuvenates Follicles Walmart.com Advanced GHK Cu Face Cream 2400mg 4% Firmer Skin Neurogan Neurogan Health Copper Peptide Hair Growth Serum 10% GHK Cu & 5% AHK Cu Hairgenetix 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