The form of GHK Cu you use may matter more than the peptide itself. Which form of GHK Cu have you personally tried before and what was the FIRST noticeable change you experienced? Why Collagen Loss Accelerates After 40: The Role of GHK Cu in Menopaus Pure & Cimple Copper Peptide GHK Cu for Sale Stanford Advanced Materials GHK Cu: The Elegant Copper Peptide for Skin and Scalp Renewal Renew Vitality GHK Cu Copper Peptide: Dosage, Before and After Results, and How It Works Perfect B