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This double-flap insulated cat flap provides excellent protection in all climates. It can be installed in wood, uPVC and glass doors. It is important to have a door that seals tightly, particularly during colder weather. It prevents warm air from being sucked away and cold air from getting in, saving money on energy costs. Wind Resistance A cat flap cover for winter can help keep your home warmer by stopping cold air from entering and allowing warm air