Insulation Sheet Insulation Material Melamine Insulation Color Gray Overall Length 8 ft Overall Width 24 in Thickness 1 in Minimum Operating Temperature -40 Degrees F Backing Type Plain Maximum Operating Temperature 350 Degrees F Facing Material Unfaced R Value 3.85 Form Sheet Flame Spread Index 25 Smoke Developed Index 50 Foam Cell Type Open Plenum Rating Plenum Rated Flexibility Flexible Standards ASTM E84 Clean Room Class Fed. Std. 100