Duda Solar propglyI Propylene Glycol (1 gallon), 1 Pack Non-Toxic Antifreeze. Use in solar water heater systems, vehicles, refrigeration applications, etc. Food-Chill Propylene Glycol, corrosion inhibitors coat metals to protect them from corrosion 99.5+% Pure Inhibited Propylene Glycol, 50/50 Solution Freezes at -29g;F Environmentally Friendly High Quality and Pure Product