Motorcraft Orange Prediluted Anti-Freeze 50/50 Coolant 3.78L

Antifreeze is a tinted liquid that you put (along with water) in your radiator to help regulate engine temperature. Its key ingredient is ethylene glycol, which lowers water's freezing point and raises its boiling point. This helps prevent the water in your radiator from freezing, boiling, or evaporating.
Water by itself can't do the job of antifreeze due to its lack of boiling and freezing point range and its inability to protect your vehicle's engine. Plus, it doesn't absorb heat as effectively. In the case of an absolute emergencyAntifreeze, or engine coolant, is a colored liquid that is mixed with water to help regulate your engine during extreme temperatures. As the temperature outside changes from hot to cold coolant is pumped throughout the engine block to maintain an even operating temperature.You aren't really protecting anything by adding water. You're just putting a weak form of antifreeze into your cooling system, which will drop the freeze point a few degrees, but won't stop it from freezing. 50/50 coolant is ready to use. Don't add water to it.