Valvoline ZEREX G-40 antifreeze coolant is premium automotive engine coolant developed by BASF AG and Valvoline. The patent-pending hybrid carboxylate formulation has an extended service life. It incorporates state-of-the-art organic acid technology in an ethylene glycol base for protection of all cooling system service life. It incorporates state-of-the-art organic acid technology in an ethylene glycol base for protection of all cooling system metals including aluminum.