Antifreeze, also called coolant, is the liquid inside your radiator. It works as a lubricant for some of the engine's moving parts, and it keeps the water in your motor and radiator from freezing in cold temperatures or boiling when the engine gets hot. The main ingredient in Antifreeze is Ethylene Glycol, and it's usually mixed with an equal amount of water. A low level of Antifreeze could cause damage to your engine, but it's easy to replace by buying more via Instacart and refilling your coolant reservoir or radiator. You should wait for the engine to cool before adding Antifreeze. You can buy concentrated or premixed versions. Ethylene Glycol can taste sweet to pets and kids, so you should never leave open containers unattended. If you spill Antifreeze, clean the area thoroughly. Look for brands with a bittering agent to make them unappealing to animals and children.