It is a combination of Calcium with Vitamin D3(cholecalciferol) which is used as bone joint supplement.  It is used to prevent or treat low blood calcium levels in people who do not get enough calcium from their diets.Calcium is important for growth and development of bones.  It  is well known for its anti-osteoporotic activity. Vitamin D3 enhances the efficiency of calcium absorption. Therefore, vitamin D3 supplementation is expected to protect against osteoporosis and fractures in those with occult vitamin D3 deficiency.