Mag OilMagnesium Oil is for use at the end of the day to promote a sense of relaxation and wellbeing through massage. Apply before bedtime to the neck and shoulder area, lower back, legs or even the bottoms of your feet. 31% Concentration Magnesium Chloride Approximately 100 mg of elemental Magnesium per 10 sprays Adults 15 30 sprays topically rubbed into the skin. You may layer the sprays or apply to multiple areas until you reach desired number of sprays.