Permatex OPTIMUM BLACK RTV silicone gasket maker combines maximum oil resistance with high flexibility. The trend is towards increasing use of dissimilar materials (plastic/steel, aluminum/steel, etc.), all which have different rates of expansion and contraction. In addition, with technology advancing, regulations and requirements tightening, designs include thinner metals, fewer fasteners, and wider spread bolt patterns.

Permatex OPTIMUM GREY® Hi-Temp RTV Silicone Gasket combines maximum torque load and vibration resistance with extreme temperature resistance: -65°F to 700°F (-54°C to 371°C) intermittent.