Longjack (Eurycoma longifolia) is often referred to as "The Malaysian Ginseng" and viewed as an important tonic herb. We use the very best quality Yellow Longjack (Eurycoma longifolia) root, Standardised 25:1 Extract, Eurycomanone 1%. The root is considered the most valuable and beneficial part of the plant due to its high concentration of bioactive compounds. Eurycomanone is believed to be the key compound that contributes to the benefits associated with Longjack and we standardise our extract to 1% Eurycomanone.