Sonic Homework Acoustic Sound Foam kit, incl. 4 Sqft. 2-in. thick Pyramid Foam with free adhesives, for studios and critical listening applications This kit includes 4 square feet of 2-inch Pyramid foam in 24-inch by 24-inch panels Sonic Homework 2-inch Pyramid-shaped acoustic foam is best for increasing dispersion as well as absorbing unwanted sound 2-inch Pyramid foam, covering 25-50 percent of the walls in your room, will help control unwanted peaks and dips in the frequency response Sonic Homework Acoustic Foam has a density of 2.0lb per cubic foot, and is class-b flame-retardant Sonic Homework kits are shipped with premium adhesive tabs for installation. Just peel the backing and hang 'em up