The patented Attic Tent consists of a durable shell made of synthetic casting, designed to create an air transfer barrier between attic and living areas. Keeps blown insulation in the attic when the attic stair door is opened. Calculated to a 3.2 R-value. The 1/2" thick micro-fiber urethane insulation, is proven to reduce air transfer by at least 71%. It fits easily around an attic stair frame.