Insulation, fiber glass, mil-i-22023, type 1, class 4, rubber coated , 1 in. Thk material, 39-7/16 in. O/a lg by 13-1/32 in. O/a w, slotted along lg 12-1/2 in. Lg by 11 in. W, slotted along w 2-1/2 in. Lg by 5/8 in. W, cut along one w 4-11/32 in. Lg by 1-3/16 in. W, one hole 2-1/4 in. Dia