Like other AAS, drostanolone is an agonist of the androgen receptor (AR).  It is not a substrate for 5α-reductase and is a poor substrate for 3α-hydroxysteroid dehydrogenase (3α-HSD), and therefore shows a high ratio of anabolic to androgenic activity.  As a DHT derivative, drostanolone is not a substrate for aromatase and hence cannot be aromatized into estrogenic metabolites .  While no data are available on the progestogenic activity of drostanolone, it is thought to have low or no such activity similarly to other DHT derivatives.  Since the drug is not 17α-alkylated , it is not known to cause hepatotoxicity . 
presents you another cutting cycle for summer which will make you look hard and solid. As a base we will use testosterone enanthate however you may replace it with testosterone propionate as in some individuals enanthate will make visible water retention but I dont think this is a problem as you dont prepare for the contest, right? 🙂 On the other hand switching to propionate will bring you another headache as you will have to inject it EOD plus you will inject Primobolan ( Methenolone Enanthate) 2-3 times per week so having to inject primo and test propionate will keep you really busy and will not give your injection sites enough time to rest.
Masteron is a highly androgenic injectable steroid that is derived from DHT (dihydrotestosterone). DHT does not aromatize to estrogen (and in fact may combat estrogenic sides), and as a result, there was no noted water retention during administration nor gynocomastia. Masteron is almost exclusively used during the last 4-5 weeks before a bodybuilding show at a dose of 100-mg every second day. Additionally, according to available literature, Masteron is not much of a mass drug, and it's always used for cutting, from what I've seen reported. Masteron has a receptor binding ability above that of testosterone, due to it's being DHT-derived, which should impart lypolytic (fat-burning) effects above that of testosterone, and also give it a nice strength building component.