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 Peptide Serum 30 ml, Copper Peptide Serum with Hyaluronic Acid for Tightening, Collagen Boosting Amazon.com: Neurogan GHK Cu (Copper Peptide) Neck & Face Serum 1,200mcg (1 oz bottle) : Beauty & Personal Care Copper Peptide (GHK Cu): Clinical Uses, Stability & Compounding Tips