(4) 20"x48"x4.375" panels, 2 MAX stands Mobile, Absorptive, eXpandable. The MAX-Wall Modular Acoustical Environment. It's everything you've always wanted from your acoustical treatments! Affordability. Portability. Expandability. Adaptability. The interlocking MAX-Wall acoustic foam panel kit system is made to grow and grow as your needs change. You want modular? MAX-Wall's your answer!