Ultra BoneUp provides StimuCal MicroCrystalline HydroxyApatite (Mcha) from free-range New Zealand calves and micronutrients to support bone health. StimuCal is a naturally derived source of calcium shown to support bone mineral density better than calcium carbonate. StimuCal also provides bone proteins, including type I and Ii collagen. Vitamins D and K work together to support calcium deposition into bones. Ultra BoneUp also includes silicon for ultra support.