Meet GHK Cu the tiny blue beauty peptide under 400 Daltons Naturally occurring, heavily researched, and known for its ability to absorb effectively due to its ultra small size. Our Sapnne Naturals 5% Ghk Cu Serum Etsy This is a product I purchased on Amazon, so I want to give it a quick review. *~Dumie GHK CU Facial Serum~* This is a Copper Peptide serum that is working amazingly for GHK Cu Topical Sky Blue Cream & Royal Blue Serum Bundle Aseir Custom Sky Blue Cream vs. Royal Blue Serum: What's the Difference? Jay Campbell