Probull is a natural probiotic. Probiotics are live microorganisms that, when taken in the right amounts, generate a positive effect on health. The quality of a probiotic is measured by the number of strains and the number of colony-forming units (CFU). Probull is made with a proprietary blend of 30 live bacterial strains from 19 species and 350 billion CFUs per gram (25 billion CFUs per capsule). Format: Bottle of 60 capsules. How to use: Take 1 capsule, preferably in the morning.