SANDERSON® Superior Total Calcium provides 270mg of elemental calcium from two bio-available sources – Calcium Hydroxyapatite and Calcium Citrate. Horsetail herb is also included to provide a natural source of silica which helps the body to 'fix' calcium stores. The formulation includes vitamin C to aid calcium absorption. Nutritional cofactors zinc, boron, manganese and vitamin K are included to aid bone mineralisation. Magnesium supports bone density, while vitamin D assists the body's uptake of calcium.