Sustanon is a mixture of four esters of Testosterone (the main male sex hormone), each ester has a different half-life in the body. If to compare Sustanon with individual forms of Testosterone, it has some advantages, for example ease of use, instead of several separate forms of Testosterone. Also, each of the 4 testosterone esters enhances each other's action. It is a mistake to consider Sustanon, as a combined cycle in one ampoule, since all of it’s active substances are Testosterones, which are different in the speed of exposure in the human body.In 250 mg. Sustanon contains:Testosterone Propionate - 30 mg.Testosterone Phenylpropionate - 60 mg.Testosterone Isocaproate - 60 mg.Testosterone Decanoate - 100 mg.