NOW Calcium Carbonate is a basic calcium supplement that contains one of the highest concentrations of elemental calcium (about 40%), making it an optimal formulation for supporting healthy bones and teeth. The Powdered form is pure, free of fillers and preservatives, much lower in cost, easy to digest and can be taken in desired potencies. Our NOW natural and organic Supplements are an effective way to ensure you and your loved ones are getting essential vitamins, minerals and nutrients for daily optimal health. Since 1968, NOW has been making top quality products that are tested to the highest standards to empower people to lead healthier lives. Our promise - what is on the label, is precisely what is in the bottle.