Fly doors, also known as screen doors or fly screen doors, are designed to keep insects and other unwanted debris out of a living space while allowing fresh air to flow in. They are typically installed on exterior doors, such as front doors and back doors, and can be customized to fit a range of door sizes and styles.

One of the key features of fly doors is their ability to provide a barrier against insects and other pests, while still allowing natural ventilation to circulate through a home or building.