Deca Durabolin 250mg is a popular anabolic steroid made up of Nandrolone and the massive Decanoate ester. Nandrolone was initially discovered in 1960, and Deca Durabolin was produced for commercial use in 1962. Nandrolone Decanoate belongs to the class II AASs, which are made up of 19-nortestosterone-derivatives. AASs are a large and fast-developing class of synthetic androgens that are used both medically and illegally. Nandrolone binds to human serum sex hormone-binding globulin (SHBG) with a low affinity, around 5% that of testosterone and 1% that of dihydrotestosterone (DHT). It is mostly metabolized by the enzyme 5-reductase into 5-dihydro nandrolone, 19-norandrosterone, and 19-noretiocholanolone, all of which are detectable in urine.