Microcrystalline Hydroxyapatite (M.C.H.A.), also known as Micro-crystalline Calcium Hydroxyapatite Complex (M.C.H.C.), is derived from raw bone and prepared by a special low temperature process (below 37 C) to preserve the protein content. The calcium thus provided is in an extremely bioavailable form. Vitamin D3 is because it is required for the absorption and utilization of calcium and phosphorus and is especially important for normal growth and development of bones and teeth. Note: #834 does not contain Vitamin K, for an MCHC product with vitamin K, see #834K.Serving Size:1 Capsule Servings Per Container: 120 Amount Per Serving % Daily Value Vitamin D3 (as cholecalciferol) 250 IU 63% Calcium (from M.C.H.A. and calcium citrate) 250 mg 25% Phosphorus (from M.C.H.A.) 56 mg 6% Boron (as boron aspartate) 750 mcg Other Ingredients: gelatin (capsule), vegetable lubricant Warnings Sold only for dispensing by a licensed health care professional. Tamper evident band around cap and seal on bottle. Do not use if either seal is broken or missing. Keep out of reach of children. Pregnant and/or lactating women should consult their physician prior to use.