Virex Valor XL Note, our products may vary in batches. Please read supplement facts prior to purchasing. We are constantly calling on advances in health science and technology to ensure we have the most refined and precise products available on the market. Virex Valor XL Male Enhancement They also found that some of the supposedly "natural" products have traces of phosphodiesterase-5-inhibitors , the medication found in prescription drugs -- such as Viagra -- used to treat impotence. And there's plenty of debate on whether size matters at all.