Dietary Supplement. 625 mg Tribulus Terrestris Extract Blend Standardized to 40% Furastanol Saponins. Optimum Nutrition 's Tribulus 625 Caps are made with the finest Tribulus Terrestris available. Each capsule contains a 625 mg blend of Tribula Terrestris powder and extract - standardized to 40% Furastanol Saponin content. Tribulus 625 Caps also contain various sterols, flavonoids, and other plant compounds that occur naturally in this species. Optimum Nutrition 's Tribulus 625 Caps are produced and packaged in our own state-of-the-art, OTC approved manufacturing facility in accordance with current Good Manufacturing Practices (cGMP's).