Highly Reflective Double Sided Radiant Barrier with a closed-cell foam core insulation. (not cheap bubble) Industrialized strength, lightweight yet durable insulation designed to hold staples without tearing. Does not compress, collapse or disintegrate. Reflects 97% of radiant heat, emits less than 3% of heat, ASTM Class 1 / Class A fire rated radiant barrier that has passed the ASTM E84 test & ASTM E2599 Non-toxic, non-carcinogenic, fiber-free, safe to handle and does not require protective clothing or respirators to install. Easy to install and maintenance free, cuts easily with utility knife or scissors and installs easier than fiberglass. Simply staple, nail, glue or use a spray adhesive to hold in place! No mess, and no itchy fibers! Not affected by moisture or humidity. Inhibits condensation and does not promote the growth of fungi, mold or mildew. Does not promote nesting of insects or rodents. Non-flammable, flame retardant Saves energy by reducing the stress on heating and cooling systems, keeping your home warmer in the winter, and cooler in the summer. It can reduce utility bills substantially all year round. As well as provides benefits of soundproofing when used in walls, ceilings and floors. Can also increase your overall property value depending on use. Specs EXTREMELY EFFECTIVE - R6 (with one layer), up to 15 (with two layers), reflect 97% of radiant energy, perfect radiant barrier!REFLECTIVE SURFACE - Metalized Film (will not oxidize like aluminum does).Water Proof (Indoor / Outdoor) VAPOR BARRIER -Unaffected by humidity and moisture, mold resistant , can be used outdoor/indoor!FOAM, NOT A BUBBLES- very easy to work with, will sealed the holes from staples or screws itself, will not lose a 3mm thickness over the time.FIRE RATE - Fire rate Class 1 / Class A, NON TOXIC - will not irritate skin, eye or throat. Non allergic.EASY TO WORK WITH - Easy to install, easy to cut and easy to clean, Strong but lightweight.Thickness (1.5MM) (1/16 nominal thickness) 4FT X 100FT = 400sqft