This product (Nandrolone Decanoate) is sold under different names:
Deca, also known as Deca or nandrolone decanoate, is perhaps the second-best known injectable steroid after testosterone. It seems that almost every steroid novice and many who are experienced with steroid cycles believe that for best results they may need to include Deca. However, in fact this compound has no special properties: other injectable steroids can do everything for muscle growth that Deca can.
The unusual properties of Deca are due to its parent steroid, nandrolone, also known as 19-nortestosterone. One of the principal positive qualities of nandrolone is that it has relatively low conversion to estrogen compared to testosterone.
In earlier years, testosterone and nandrolone were the only pharmaceutical injectables that were both widely available to bodybuilders and economical. Estrogen control did not then exist. For this reason, Deca’s low aromatizing properties were then quite useful. Deca therefore won wide popularity.