The Dow electrolytic cell is a steel shell about 16 ft (4.88 m) long, 5 ft (1.52 m) wide, and 6 ft (1.83 m) deep. The electrolyte contains about 60% NaCl, 15% CaCl₂, and 25% MgCl₂; it is maintained at a temperature of 700 to 750 degrees C by controlled firing underneath the cell.