Ultra Bone-Up(R) from Jarrow Formulas(R) provides StimuCal Microcrystalline Hydroxyapatite (MCHA) which is from free-range New Zealand calves and includes the superior combination of the inorganic calcium lattice of MCHA within the organic protein. StimuCal is combined with Vitamin D-3 and Vitamin K-2 (as MK-7 from a natural fermentation process) and JarroSil(R) silicon to support deposition of calcium into the bones as well as assisting in the bone matrix. Formulated for quick absorption.