(4 Pk) 12"x12"x12" Soundproofing Foam Acoustic Bass Trap Corner Studio Foam Sound Wedges Great performance at a Low Cost Smaller panels offer more options for placement and design Very Good Quality High NRC ! Reduces standing waves and flutter echoes in small to medium sized rooms Eliminates Standing Waves And Flutter Echoes ; Reduces Unwanted Reflections; Reduces Unwanted Reflections