The most commonly used AAS in medicine are testosterone and its various esters (but most commonly testosterone undecanoate , testosterone enanthate , testosterone cypionate , and testosterone propionate ),  nandrolone esters (most commonly nandrolone decanoate and nandrolone phenylpropionate ), stanozolol , and metandienone (methandrostenolone).  Others also available and used commonly but to a lesser extent include methyltestosterone , oxandrolone , mesterolone , and oxymetholone , as well as drostanolone propionate , metenolone (methylandrostenolone), and fluoxymesterone .  Dihydrotestosterone (DHT; androstanolone, stanolone) and its esters are also notable, although they are not widely used in medicine.  Boldenone undecylenate and trenbolone acetate are used in veterinary medicine . 
Sustanon is made up of 100 mgs of testosterone decanoate which has a half life of 14 days. The next drug in Sustanon is 60 mgs of testosterone isocaproate which has a half-life of 8 days. The third drug is 60 mgs of testosterone phenylpropioate with a 6 day half life. And finally the last ester is testosterone propionate which has a half life of 4 days. So not only is it extremely difficult to map out the life of these different testosterone esters, but in addition, Sustanon is only dosed at 250 mgs per ml. This means that if you are using ampoules of Sustanon (the little bullet shaped class vial in the pic next to the box), you have no choice but to dose the drug in multiples of 250mgs.