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A cat flap made of UPVC allows your cats to come and leave at their own pace. It's a simple three-step installation procedure that can be fitted into glass doors, wooden doors, or UPVC panels. This is a great choice for those who want to keep their pets secure and save money on energy. UPVC panels can resist heat, moisture and UV. Easy to install Installing a pet flap over your glass door or glass panel is a great idea if you have a kitty. This is a great solution to ensure your pet's safety when you're awa