Ethanol-free, safe, odorless, tasteless, and non-flammable premium hyrdronic heating and cooling system fluid. Made from virgin propylene glycol (PG), this heat transfer fluid contains premium corrosion inhibitors to protect internal components. It’s formulated to have a high specific heat and boiling point, and provides burst protection down to -100ºF (-73ºC) at full strength. Works in Aqua-Hot® and Hydro-Hot® systems as a heat transfer fluid, and is perfect for use in traditional boilers, closed boilers, and solar systems. Made in the USA.