Ultra-D Complex™ offers vitamin D (cholecalciferol) with its key cofactors in a base of cod liver oil, which is a natural source of vitamin D, vitamin A, EPA (115 mg), and DHA (95 mg). This formula is designed to support the metabolism of vitamin D and to deliver a powerful mix of supportive nutrients.* This advanced formula includes (2000 IU) 50 mcg of vitamin D per serving (in a pleasant orange flavor without an unpleasant fishy taste). Other nutrients, such as magnesium, biotin, pantethine, calcium, and boron, are all incorporated in this formula. Also available, Ultra-D 5000™ (K78) with (5000 IU) 125 mcg of vitamin D per serving.