GHK Cu is one of my personal favorites for a lot of reasons, but I can say without a doubt that it's use effectively stopped and reversed, my receiving hairline. However, there are GHK Cu vs NAD+: Which Longevity Peptide Should You Take or Stack? GHK Cu Copper Peptide 0.5% (topical foam) Shell Medical 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