glutathione and l cysteine L-glutamate L-cysteine are bound by glutamate–cysteine ligase L-Glutathione w/L-Cysteine - BOSCOGEN, INC.
Description
This copper peptide (GHK-Cu) is a stable, lyophilized powder designed for controlled research applications

20% uncertainty applies
New York: Harper & Row

I also used it for the P3 stage and swear by it

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