Windmill Vitamin D 400 IU Tablets Dietary supplement. Helps develop strong bones and teeth. No sugar, starch, yeast, wheat, milk, soy, artificial flavors or preservatives. Our Vitamin D provide 400 IU of cholecalciferol per tablet. Cholecalciferol, otherwise known as D3, is the vitamin D that is formed when the sun touches human skin. For additional formula information, view the Supplement Facts panel. All Windmill supplements are manufactured in the United States in an FDA-inspected facility whose GMPs (Good Manufacturing Practices) are independently verified by qualified certification organizations. Free of artificial colors, flavors and preservatives, Windmill is a trusted name that has been providing America with quality supplements for over 40 years.