Pharmaceutical Name: Stanozolol 
Chemical structure: 17 alpha-methyl-5alpha- androstano [3,2-c]pyrazol-17 beta-ol 
Molecular weight of base: 344.5392 
Effective dose: 50-100 mg/day injection or 50-100 mg/day orally 
Available Doses: 2, 5 and 10 mg tabs or 50-100 mg/ml

Winstrol is a popular brand name for the anabolic steroid stanozolol. This compound is a derivative of dihydrotestosterone, although its activity is much milder than this androgen in nature. It is technically classified as an anabolic steroid, shown to exhibit a slightly greater tendency for muscle growth than androgenic activity in early studies. While dihydrotestosterone really only provides androgenic side effects when administered, stanozolol instead provides quality muscle growth. Admittedly the anabolic properties of this substance are still mild in comparison to many stronger compounds, but it is still a reliable builder. Its efficacy as an anabolic could even be comparable to Dianabol, however Winstrol does not carry with it the same tendency for water retention. Stanozolol also contains the same c17 methylation we see with Dianabol, an alteration used so that oral administration is possible. To spite this design however, there are many injectable versions of this steroid produced.

Stacking and Use: 

Winstrol is best used at a rate of 50 mg a day. When in an injection that amounts to a single injection every day around the same time. In orals, that'll be at least 5 tabs of a legit product. 

In a mass stack Winny makes a good match for Deca and Nilevar. Whether or not its anti-progestagenic effects are for real or not, lets just say it can't hurt. In any stack with Deca the use of 25-50 mg a day for the first 6-8 weeks of the stack can kickstart it and add some strength. With Nilevar there is a practical objection because it is also 17-alpha alkylated and more toxic than Winny, so your stack would be limited to 6 weeks, which is not overly productive.