Methylene Blue 1% USP Grade Bottle 2oz. Ultra Pure - Glass Bottle Volume: 2 fluid oz or 56 ml Purity by UV 100.4% Grade USP Heavy Metal Free CAS: 7220-79-3 Molecular Formula : C16H18ClN3S Each ml equals 10mg of Methylene Blue or .5mg per drop. 20 drops per ml. Please visit manufactures web site at Neurobluesolutions to learn about all of the amazing uses of this product. 2 year shelf life. Store away from light and heat.