https://gustavsen-palm-3.hubst....ack.net/using-upvc-c
Cats love looking out of windows, which is a form of entertainment sometimes called cat TV. It is a type of entertainment that is usually instinctual. Glass window inserts with cat flaps to existing windows or doors. They can be installed in double glazing. Easy to install Cat flaps can be attached to any type of glass including patio doors, french doors, bifolds, and single-glazed windows. They are great for people who do not want to cut into a door or wall and wish to allow their pet access to windows. Y