UGS1188: Features: -Wall sleeve. -Use with through-the-wall air conditioner. -Securely fastened to wall opening before installing air conditioner. -Helps bear the weight of the air conditioner and insulate the air conditioner. -Protects the air conditioner from dust, bugs and other debris that could get sucked into it. -All metal construction withstands inclement weather, corrosion and other elements. -Pre-cast concrete or masonry walls.