Helloskin GHK Cu 1% Triple Peptide Regenerative Serum Topical or SubQ GHK Cu? Same molecule. Very different purposes. Topical you apply it on your skin. Think of it as feeding your skin from the outside. In a 12 week study of Ghk Cu Shampoo Copper Peptide Hair Growth Best Peptide for Hair Growth Copper Peptide Shampoo Copper Peptide Hair Growth Serum AHK Cu & GHK Cu + Licorice Peptide Labz Neurogan Health, GHK Cu Copper Peptide, Hair & Scalp Serum GHK Copper Peptide GHK Cu Tripeptide 1