The PetSafe® Pet Screen Door snaps directly into your existing screen door, window or porch screen for quick and easy installation. The door is reinforced with fastening screws to ensure a sturdy attachment for large pet use. This swinging pet door is built with a high-impact plastic frame. Sliding locks prevent the flap from moving in inclement weather, but open if a pet runs through. The durable mesh material is designed specifically to stand up to frequent use from dogs or cats. The Pet Screen Door blends perfectly with your existing screen door while providing convenience for you and your pets.