HGH, IGF1-LR3, Insulin, Melanotan, GHRP, MGF and the list goes on and on and on. They're very interesting. Made of long chains of protein and some stimulate muscle growth, others stimulate differentiation of stem cells in to muscle cells, MGF can make a muscle grow big time if injected directly in, GHRP increases your growth hormone production, Melanotan makes you tan, Insulin you should know. Good stuff, I'm dying to try them. Most have to be refridgerated, injected SubQ and are very delicate with short shelf lives.