Pure Bulgarian Tribulus Terrestris - 95% Steroidal Saponins, 80% Protodioscin, Max Strength, Highest Potency On The Market, Increases Libido, Endurance and Stamina to Promotes Muscle Gain - 1300mg by Nutrarise The manufacturer claims 80% content of furastanol saponins (or ? 500 mg of Protodioscin/capsule) determined as Protodioscin. The testing method used : nuclear magnetic resonance spectroscopy Results : 3.4