Pentofrost A1 HOAT phosphated antifreeze is specifically formulated for Asian vehicles. Meets the requirements for Toyota, Lexus, Scion models requiring RED antifreeze. Pentofrost A1 is a phosphated organic acid technology (phosphated OAT); which is categorized as HOAT (hybrid organic acid technology) in the US market. Pentofrost A1 is suitable for all Asian vehicles using âredâ? Antifreeze/Coolant. Pentofrost A1 does not contain any silicate, borate, nitrite or amine containing additives since these may harm your Asian vehicle. Do not mix with other coolants (especially silicated coolants), as this may cause ge formation and clog your radiator. Pentofrost A1 is an antifreeze PRE-DILUTE for Asian vehicle applications in water-cooled engines. Do not mix with water. It contains phosphates and organic salts to protect all materials used in cooling systems for Asian vehicles. Pentofrost A1 is mixable with all phosphated OATs. Meets ASTM D-3306. Ready to use with the correct 50/50 dilution of concentrate OE formulation and DI-WATER (Deionized). Application specific to ensure you get the right Antifreeze that is required for your vehicle and specified in your owners manual. H-OAT inhibitor package (Hybrid Organic Acid Technology). Engineered in Japan / bottled in the USA