Copper Peptide Hair Growth Serum 10% GHK Cu & 5% AHK Cu Hairgenetix 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 12 weeks in, and my skin has NEVER looked better! GHK peptides are doing their thing. Alright, I need to give you an updateit's been 12 weeks since I started using GHK 12 weeks in, and my skin has NEVER looked better! GHK peptides are doing their thing. Alright, I need to give you an updateit's been 12 weeks since I started using GHK GHK Cu, the copper peptide, is a game changing injectable for radiant skin and so much more, , , Heres what it can do:, Boost collagen for smoother, firmer skin, Anti aging improves fine