Neurogan Copper Peptide Hair Scalp Serum for Fuller Softer Shinier Hair Walmart.com Copper Peptide Serum for Hair Regrowth & Thinning Hair Feline Skinscience Amazon.com: Neurogan GHK Cu + AHK Cu Hair Serum Pro Lightweight Scalp Serum with Dual Copper Peptides Daily Hair & Scalp Use, Cosmetic Product : Beauty & Personal Care 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