This product is a 20X concentrated stock solution and should be diluted appropriately with distilled, deionized water or equivalent to its final working concentration. This buffer consists of 3.0 M Sodium Chloride, 0.2 M Sodium Hydrogen Phosphate, 0.02 M EDTA at a pH of 7.4. Meticulously prepared using ultra pure reagents dissolved in highly polished pharmaceutical grade deionized water treated with diethyl pyrocarbonate (DEPC).