Not all Copper Peptides are created equal If you've tried copper peptides before and saw no change, here is why: Concentration and Stability. Most serums use a diluted solution that barely scratches GHK Cu vs AHK Cu: Which Copper Peptide Is More Effective? Amazon.com: Jkrova GHK Cu Copper Peptide Face Cream 4% Peptides Moisturizer for Fine Lines, Wrinkles, Firming, Deep Hydration & Collagen Support 2400mg GHK Cu for All Skin Types, 30g : Beauty Thrive Copper Peptide Serum Skin Barrier Support & Hydration 29ml 7% GHK CU ACCELERANT Platinum Skin Care