Not long ago, coolant leaks required immediate repair. But these days, leaks may go unnoticed until the vehicle starts to seriously overheat. To better meet these evolving challenges, Bar's Leaks® has reformulated its popular Liquid Aluminum™ Radiator Stop Leak into a next-generation stop leak for the entire cooling system. New Bar's Leaks Liquid Aluminum Cooling System/Radiator Stop Leak (p/n 1186) has been specifically formulated to permanently seal the coolant leaks that cause most overheating problems. It now features the proprietary wetting agent Xtreme Cool®. Xtreme Cool reduces the surface tension of coolant - which increases its wetting ability - as well as improves heat transfer and reduces coolant temperature.