Testosterone suspension is one of the top choices of bodybuilders and athletes when it comes to steroids. This is because this steroid provides the fastest and best results in terms of body mass building and one of the most effective steroids for bulking up. Testosterone suspension is an injectable preparation containing unesterfied testosterone in a water base. Among athletes, testosterone suspension has a reputation of being an extremely potent injectable, often ranked highest among the testosterones. Very fast acting, testosterone suspension will sustain elevated testosterone levels for only 2-3 days.