https://historydb.date/wiki/Fitting_a_Cat_Flap
This cat flap is insulated and features a double-flap design and provides a high level of protection in various climates. It can be installed in wood, uPVC, glass, and metal doors. A tightly sealed door is vital, especially in colder weather. It stops warm air from being sucked away and cold air from getting in, saving money on energy costs. Wind Resistance Using a cat flap cover for winter will help keep your home warm by blocking cold air from entering and keeping warm air within. Most of the best options are insulated and have a magneti