Sonic Homework Acoustic Sound Foam kit, incl. 8 Sqft. 2-in. thick Pyramid Foam with free adhesives, for studios and critical listening applications 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 Sonic Homework kits are shipped with premium adhesive tabs for installation. Just peel the backing and hang 'em up.