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 Premium Air Conditioner Insulating Seal is a high-density foam that creates a weather-tight seal around your air conditioner unit, keeping winter and summer drafts from entering your home. In addition to keeping the cool air in and warm air out, they reduce noise and vibration while helping to block 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.