500 MG Standardized Extract Vitality* Tribulus terrestris has been used for centuries in ancient Greece, India and Africa to enhance vitality and virility.* Recent research indicates that tribulus can support the body's free radical defense systems and preliminary studies suggest that tribulus may help to promote healthy endocrine function and male reproductive health.* If you are a competitive athlete who is regularly tested, please check with your sanctioning body for the status of tribulus. Natural color variation may occur in this product.