500 SQUARE FEET ROLL (14 pounds): 125 linear feet BREATHABLE (perforated) DOUBLE-SIDED metalized aluminum film ASTM C1313 certified radiant barrier; reflects 99% radiant heat USED IN RETROFIT & NEW CONSTRUCTION: Reduces residential attic temperatures up to 40 degrees; lowers utility bills year round. Thermal insulation used in attic space, garage, garage doors, house wrap, workshop, shed, storage unit, commercial metal building, pole barn, as pallet wrap, and more Heavy Duty No Tear: Radiant barrier designed for residential retrofit installations on attic floor (can withstand stapling like Radiant barrier Ultima or Xtreme Series). EASY TO MAINTAIN: Non-toxic; non-carcinogenic; fiber free; easy to install; not affected by humidity; maintenance free ASTM CERTIFIED: Meets all American Society for Testing and Materials (ASTM) requirements for radiant barrier classification (C1313) Exceeds all FIRE, SMOKE, (ASTM E-86) and BREATHABILITY requirements for building materials (ASTM 96-00). BLOCKs 99.06% of RF signals (IEEE-299) for Sensitive Compartmented Information Facility SCIF rooms