This easy-to-install foam seal closes the gaps between the window A/C 
 unit and window frame, keeping outside air, insects and dust out.
 
 Duck 18 in x 9 in x .88 in Window Air Conditioner Insulating Panels: 
 Window
  air conditioning units can provide added comfort in the hot summer 
 months, but can also create a gap that lets in outside air, dust, 
 insects and pollen. Duck Brand Air Conditioner Insulating Seals are 
 easy-to-install foam seals that close the gaps between the window A/C 
 unit and window frame. In addition to keeping the cool air in and warm 
 air out, they reduce noise and vibration while blocking unwanted dust, 
 insects and pollen from entering your home. Use together with other Duck
  Brand weatherization products to make your home more comfortable and 
 energy efficient all year long.
 Insulating foam seal
 Easy to install
 Use with window A/C units