SPECS: 72 inch wide x 50 ft LONG / R8 / 5MM THICK / DOUBLE SIDED Will not lose its performance and provides a vapor barrier Blocks radiant heat by up to 99.7% Reduces Heating and cooling loss / Saves you Energy and Money Easy to use and install / Made in the USA Highly Durable, Lasts Longer NON-TOXIC, WILL NOT IRRITATE SKIN, EYE, OR THROAT 5mm Reflective Thermal Insulation Foil Foam Core Double Sided Radiant Barrier (Cold & Heat Shield): Attics Ceilings Walls Steel Buildings Roofing Warehouse Crawlspace Etc (72"x50') (R8 / Meets ASTM Fire Codes)