GHK Cu Copper Peptide Hair Tonic for Fuller Looking Hair 12 Week Supply (30 mL) Small molecules. Powerful results. Experience Peptide Power with Hairgenetix's advanced Copper Peptide Hair Growth Serum, formulated with 10% GHK Cu and 5% AHK Cu to support hair health at the follicle level. Helps Not all hair serums are built the same This one is powered by a dual copper peptide system GHK Cu + AHK Cu Designed to support: stronger feeling hair improved elasticity Neurogan + Health GHK CU Copper Peptide Hair and Scalp Serum