Your Cooling System's Best Defense Durex's® antifreeze/coolant products provide dependable and everyday protection of your vehicle's cooling system, while meeting or exceeding industry specifications. You can trust Durex® to keep your vehicle at its best with year-round protection against freeze, boil-over, rust and corrosion. Durex® antifreeze / coolant products are compatible with all major American brands of conventional antifreeze/coolants.