The Energy Supplements Dietary Supplement Bioavailable D3 Active Form Gluten-Free Quality · Natural · Supplements Meets Strict Government Safety Standards for Heavy Metal & Toxins Vcaps Purity Guaranteed Nutritional Support for Healthy Bones, Natural Energy Production and Overall Well-Being. Nature's Plus Vitamin D3/Vitamin K2 employs the most bioavailable and effective nutrients forms of these essential bone nutrients, for optimal absorption and utilization: vitamin D3 (cholecalciferol) and vitamin K2 (menatetrenone). Nature's Plus Vitamin D3/Vitamin K2 conforms to the strictest standards for purity, including California's Proposition 65.