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https://josefsen-ross.mdwrite.....net/cat-flap-install
If you have a dog or cat, installing a pet flap inside your French or patio doors is a good idea. It allows them to get in and out without having to open the door. There are many options for cat flaps that are designed to be used with uPVC composite or wooden doors. Some come with a four-way locking system which can be set to exit only, in-only, or open. Installation C