Owens Corning 703 FRK Rigid Fiberglass, 2 inch, Case of 6 This is Owens Corning 703 FRK rigid fiberglass board in a case of 6 24 x 48 x 2 inch pieces. The FRK (Foil Reinforced Kraft)facing is a popular option for creating bass traps. The foil facing will reflect some of the mid to high range frequencies, but allows the low-end frequencies to pass through to the absorption material. Currently ships within: Same day or next business day.