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This double-flap insulated cat flap provides excellent protection in all climates. It can be fitted in wood, uPVC, glass, and steel doors. It is important to have a door that seals tightly, especially during colder weather. It can prevent warm air from getting sucked out and cold air getting in and causing you to pay more energy costs. Wind Resistance Covering your cat's flap for winter will help to keep your home warm by stopping cold air from entering and keeping warm air within. The best option