Formally known as Ultra K2 (Menatetrenone) Ultra K2 provides 15 mg of vitamin K2 in the MK-4 form. Although vitamin K2 is best known for its benefits to postmenopausal bone health due to its lack of estrogenic effects, it also supports cardiovascular health by improving the body's ability to transport calcium to the bones, and it improves joint mobility and flexibility by promoting cartilage health.*