Trenbolone is a highly effective Androgenic Steroid. Originally it was produced and made for vets, for use in animals like cattle. They would use this to help the animals gain lean weight. They were not taken orally, the pellets that were given to these animals where injected from a pellet gun. Bodybuilders started to use this to build muscle mass, by using FINA pellets. This was the original way of using the product, by turning it into an injectable, or also crushing these pellets up mixing them with a gel and rubbing it onto a body part, allowing it to be taken via transdermal use.