* L-Carnitine Tartrate * Dietary Supplement * Carefully Manufactured in the USA by: ON * The Bigger Picture L-carnitine is synthesized from the essential amino acids lysine and methionine. Because approximately 98% of the body"s L-carnitine supply is found in muscle mass, and the nutrient needs of active adults outweigh those of inactive people, ON offers this L-carnitine supplement providing 500 mg of pure L-carnitine per 1-tablet serving.