Clostebol

Clostebol (INN), usually as the ester clostebol acetate or clostebol enanthate, is a synthetic anabolic androgenic steroid. Clostebol is the 4-chloro derivative of the natural hormone testosterone.

It is a weak anabolic steroid which was used by athletes from the German Democratic Republic (East Germany). It is a version of testosterone that is chlorinated so as to prevent conversion to dihydrotestosterone (DHT) while also rendering the chemical incapable of conversion to estrogen.