https://postheaven.net/groused....ust70/cat-flap-insta
A cat flap made of UPVC lets your cats go and go whenever they want to. The installation process is a three-step process that can be done on wooden doors, glass panels or UPVC panels. This is a great option for pet owners who want to ensure their pets are secure and reduce energy costs. UPVC panels can resist heat, moisture and UV. Easy to install If you have a cat, you might want to think about installing a pet flap inside your door or glass panel. This is a great way to ensure your pet's security while you're away