L-Carnitine Fumerate 250 mg, 120 Capsules, Source NaturalsL Carnitine from L carnitine fumarate. . L Carnitine is important for providing energy to muscles, and has been described as a "conditionally essential" nutrient for humans. 95% of all carnitine stores in the body are found in muscle tissue. It carries fatty acids into the mitochondria of each cell, where they are oxidized and stored as ATP, a prime energy fuel. Supplement Facts Serving Size: 1 Capsule Amount %DV L Carnitine (as L carnitine fumarate)