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 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. This formula is also available in 5000 IU of vitamin D per serving in Ultra-D 5000™ (K78).