Nutricost's L-Arginine powder uses only high quality L-Arginine and come with Nutricost's 30 day satisfaction guarantee. Nutricost, located and headquartered in the USA, only uses the best ingredients for maximum quality and to help you feel your best! By keeping our supplement recipes simple and clean, you get the best experience possible with Nutricost. Our supplements are manufactured in a GMP-compliant and FDA-registered facility; and each batch of every product is tested by independent, ISO-accredited laboratories. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.