GFBN is a standard material used in automotive and marine under-the-hood, heater and coolant applications. GFBN's enhanced impact resistance results from inclusion of uniformly dispersed glass fibers that add strength to the resin: automotive industry approvals. Temperature Range -50 °F to 275 °F (135 °C). Pressure 150 psi at 70 °F. Heat Deflection Temperature - ASTM D64: 475 °F (246 °C) at 264 psi.