Keep metals protected from extreme weather with this concentrated antifreeze coolant from Zerex. This 50/50 antifreeze coolant has a freezing point of -34 degrees and boiling point of 226 degrees. The specific gravity is 1.124 and the pH is 9. This 1 gal. red antifreeze coolant meets standards: ASTM, SAE. Its applications include: Proprietary heavy-duty formula is meant to protect diesel engines from liner pitting and hardwater scale deposits. At max. service life, add Extended Life Extender No. 4NPP7 to stretch drain interval to 600,000 mi./14,000 hr./6 yr. OAT formula. 300,000 mi./7000 hr./3 yr.