Amazon.com: Skin Perfection Copper Peptide Serum GHK CU 1% for Face & Hair Copper Peptides for Skin, Hair, & Scalp 1% Blue Liquid for Face, Neck, Body, Scalp Multi Use Serum Booster with GHK Copper Peptide GHK Cu Tripeptide 1 GHK Cu Facial Serum Empower Pharmacy GHK Cu (copper peptide) used topically is one of the most well studied skin repair peptides. Here's how it helps the skin, in practical terms: 1. Boosts collagen & elastin GHK Cu signals your skin