At Probulin, we believe you should look for: Correct CFU’s (10 to 20 Billion CFU is all that is truly needed) Robust probiotic strains Prebiotics, like Inulin, to nourish probiotics “Cold + Protected” packaging & shipping so the probiotic products arrives alive. Scientifically studied delivery system demonstrated to ensure a greater number of surviving beneficial probiotic bacteria — We believe the ultimate delivery system is MakTrek-3D which goes beyond other probiotic delivery systems.