Valvoline™ ZEREX™ HD Nitrite Free Extended Life Coolant (ELC) is registered to Cummins® CES-14603, conforms to ASTM D6210 and is suitable for common heavy duty diesel engine requirements. Fully formulated ZEREX Nitrite Free ELC incorporates organic acid technology to protect diesel engines from liner pitting and hard water scale deposits.  The silicate and nitrite free extended life chemistry helps protect all cooling system metals from corrosion including aluminum. ZEREX Nitrite Free ELC can also be used in gasoline engines, stationary power, marine, natural gas, and light duty applications. ZEREX Nitrite Free Extended Life Coolant provides up to 6 years / 600,000 miles / 12,000 hours of service without the need for extenders due to non-depleting organic acid technology.  It is backward compatible for all cooling systems using OAT coolants.  ZEREX HD NF ELC offers enhanced protection for aluminum cooling system components.