HP- Deca Durabolin 500mg 10ml is an injectable anabolic steroid used to increase muscle size and strength. It contains Nandrolone Decanoate, a steroid hormone derived from testosterone. This hormone works by promoting protein synthesis, enabling the body to retain more nitrogen and build strength and muscle. It also improves red blood cell production, giving the athlete or bodybuilder greater stamina and endurance. HP- Deca Durabolin is usually injected directly into the muscles, usually in the buttocks, and can make dramatic changes in both strength and size in just a few weeks.