The GHK Cu pen works. But needles at home were never the answer. We took the same clinically backed copper peptide complex and put it into a serum you can use in 30 seconds, GHK Cu (Copper Peptide) Deep Dive: Mechanisms, Benefits, Risks, Forms, & Dosing Achieve Thicker, Healthy Skin with GHK Cu (Copper Peptides). Vitali Skincare GHK CU Copper Peptide, Face Serum, 1 oz (30 ml)