Copper Peptide Hair Growth Serum AHK Cu & GHK Cu + Licorice Peptide Labz Most people hear about GHK CU in beauty circles. Skin. Hair. Collagen., What they do not tell you is that this peptide is one of the most versatile in the space. I use it primarily for recovery and MOST EFFECTIVE Scalp Serum Hair Growth Factor 5% GHK CU Copper Peptide Rosemary Copper Peptide Hair Growth Serum AHK Cu & GHK Cu + Licorice Peptide Labz