The LG 26 in. Wall Sleeve/Stamped Aluminum Rear Grille for Thru-the-Wall Air Conditioners is a perfect addition to any through-the-wall air conditioner set up. The 26 in. wall sleeve should be securely fastened within a wall opening before installing the air conditioner. The AC wall sleeve helps bear the weight of the air conditioner while keeping it insulated and safe from dust, bugs and other debris that could get sucked into it. Inclement weather, corrosion and any other elements cannot match the protective power of this metal sleeve. The stamped aluminum rear grille is generally used to prevent damage to the back outer coils of the air conditioner and for keeping birds and small animals from nesting in the wall sleeve. Backed by a 1-year limited warranty, you can rest assured that this AC wall sleeve is ready to house your air conditioner.