Castrol Radicool P-OAT is a nitrite, amine, borate and silicate free antifreeze coolant for vehicles requiring Phosphated Organic Additive Technology (P-OAT). Aqueous solutions of Castrol Radicool P-OAT act as both antifreeze and coolant and offer excellent corrosion protection to all metal parts found in the cooling systems of internal combustion engines. Castrol Radicool P-OAT should be used at concentrations of between 33% and 50% dilution with distilled or de-ionised water to give optimum corrosion protection and freezing protection between -16°C and -37°C.