AHK CU + GHK Cu Hair Serum Pro 4800mg Hair Growth Neurogan GHK Cu Focal Point Vitality Indigo Glow Copper .2% Peptide Renewal Serum .25 Natural Plastic Bottle with White Flip Cap and Seal Defy GHK Cu (glycyl L histidyl L lysine) is a naturally occurring copper binding peptide found in human plasma. As levels decline with age, so may its support of the biological processes involved in collagen production, skin