24% Standardized Extract With Eleuthero Root NOW® Gingko Biloba Extract is standardized to min. 24% ginkgoflavonglycosides and 6% terpene lactones. The extract comes from the leaves of the famous Ginkgo tree with its dynamic history of populating the earth for millions of years. This double strength product has twice the ginkgo (120 mg) as in our regular strength product (60 mg). Natural color variation may occur in this product.