Compatible with all 26-inch wide through-the-wall air conditioner units: This sturdy and durable white wall sleeve can be used with any 26-inch wide thru-the-wall air conditioning unit so there's no guess work or questioning when it's time to install Protective Air Conditioner Sleeve: Blocks bugs, dust, and other debris from potentially being sucked into the air conditioner as it operates Insulates and Secures: This wall sleeve provides extra insulation to your air conditioner to keep it running smoothly and efficiently; Helps bear the weight of the air conditioner Strong and Durable: The all metal construction withstands inclement weather and corrosion and is strong enough to bear the weight of the through-the-wall air conditioner in pre-cast concrete or masonry walls up to 17.75 inches thick Wall Sleeve Dimensions: 17.5"L x 25.5"W x 15.25"H; A perfect choice to preserve these following Keystone through the wall air conditioners: KSTAT08-1C, KSTAT10-1C, KSTAT10-2C, KSTAT12-1C, KSTAT12-2C