Amazon.com: Skin Perfection Copper Peptide Serum GHK CU 1% for Face & Hair Copper Peptides for Skin, Hair, & Scalp 1% Blue Liquid for Face, Neck, Body, Scalp Multi Use Serum Booster with AHK Cu vs GHK Cu Difference Between GHK Cu and AHK Cu Perhaps the most commonly asked about question when it comes to GHK Cu is THE BURN. Let's learn! @summitrejuvenation Peptide GHK CU Cream Concierge MD Amazon.com: GHK Cu Copper Peptide Supplement, Anti Aging & Hair Growth Support, Improves Skin Elasticity & Firmness, Thicker, Fuller Hair, Easy Absorption, Precisely Dosed, 90 Vegan Capsules : Health & Household GHK Cu Copper Peptide Benefits, Uses & Safety Intra V