Quick view Douglas Products Douglas HTF Inhibited Propylene Glycol MSRP: $41.096 - $215.366 Douglas HTF Inhibited Propylene Glycol in 1 Gallon Containers Recommended for: Block Ice MachinesCirculating Beer SystemsClosed Water Loop Refrigeration SystemWood Boiler SystemClosed Loop... MSRP: $41.096 - $215.366 Quick Add Add to Wish list