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 Small molecules. Powerful results. Experience Peptide Power with Hairgenetix's advanced Copper Peptide Hair Growth Serum, formulated with 10% GHK Cu and 5% AHK Cu to support hair health at the follicle level. Helps Copper Peptide Hair Growth Serum (10% GHK Cu + 5% AHK Cu) 30ml ROBYN'S TACK ROOM 2% GHK CU Copper Peptide Serum for Hair Growth and Scalp Care Seraphime