Insul-Dome Pull Down Attic Stair Cover R-8, constructed of fire-rated 1" thick foil-faced polyisocyanurate board Incorporates Q-Lon brand gaskets and Velcro brand tie-downs to provide an air-tight seal Inside dimensions are 27" wide, 58" long, and 10" deep Comes in a kit, only requires scissors and a hammer for assembly and installation Get the same air-seal as the Therma-Dome Pull-Down Attic Stair Cover with 25% less weight