Not all copper peptide serums are formulated the same Before you buy one, make sure you're actually getting pure GHK Cu at the right concentration not just a diluted blend. We spent Glow Blend Regeneration, Recovery & Skin Renewal 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 GLOW: BPC 157 TB 500 GHK Cu Blend The Aesthetics Co.