Topical GHK Cu: Skin Benefits, Best Forms, and Where to Buy GHK Copper Peptide GHK Cu Tripeptide 1 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 They said the Topical Copper Peptide is Cope so we had to show them that it really work!, This maybe is the strongest Topical version in Europe ( 3% Blue Copper Peptide Complex ) , Only found at:,