• Versatile Fit: Accommodates TOSOT PTAC units and other standard-sized 42 x 16 packaged terminal air conditioners or packaged terminal heat pumps; a universal replacement for other major brands' wall sleeve • High-Quality Material: Utilizes hot-dip galvanized steel for robust support; prevents pressure on the PTAC or PTHP units; corrosion and rust resistant • Inner Sponge: Soft and thick; reduces vibrations and dampens noise; long-lasting protection • One-Person Assembly: Includes a top plate, bottom plate, two side plates, a pack of screws, and an instruction manual; arrives unassembled for simple installation • Wall Opening Requirement: At least 16 ¼ in length and 42 ¼ in width; modular within a height of two courses of concrete block, six courses of standard brick, or five courses of jumbo brick and a width of approximately three stud spaces