Bar’s Leaks introduces Professional Carbon Fiber Block Seal Head Gasket & Cooling Sealant (No. HG-1). The exclusive Bar’s Leaks formula combines liquid glass (sodium silicate) with aramid and refractory fibers: the same super-strong, heat-resistant materials used in bulletproof vests and fireproof clothing. The formula is further reinforced with carbon fiber to bridge larger leaks and create a truly permanent seal that is stronger than the original head gasket itself. Bar’s Leaks Head Gasket amd Cooling Sealant also features the proprietary wetting agent Xtreme Cool, to reduce the surface tension of coolant, increasing its wetting ability, and improve heat transfer and reduce coolant temperature.