Reco-Cool HD Premium-N 25% Pre-Diluted Antifreeze/Coolant is a low-silicate, nitrited, hybrid organic acid technology coolant designed for both automotive and heavy-duty diesel engines. It is pre-diluted, ready to use, and does not require additional supplemental coolant additives (SCA) during the initial fill. Free from phosphates and amines, it is suitable for petrol and diesel engines, especially in applications requiring a nitrited, low-silicate hybrid coolant. This product should not be further diluted with water.