GHK Cu for Hair Growth? It Works But Only If You Do It Right. Everyone's talking about GHK Cu, but here's the catch most serums never make it past your scalp barrier. PeptideLabz Copper Peptide 10% GHK CU 5% AHK CU Peptides Hair Growth Treatment Serum, Blue Price GHK cu Copper Peptides Serum for Hair Hair Oils Martinique Ubuy Ghk Cu Shampoo Copper Peptide Hair Growth Best Peptide for Hair Growth Copper Peptide Shampoo